IBM DataPower ALG Security Technical Implementation Guide

Successful authentication must not automatically give an entity access to an asset or security boundary. The lack of authorization-based access control could result in the immediate compromise and unauthorized access to sensitive information. All DoD systems must be properly configured to incorporate access control methods that do not rely solely on authentication for authorized access. Authorization is the process of determining whether an entity, once authenticated, is permitted to access a specific asset. Information systems use access control policies and enforcement mechanisms to implement this requirement. Authorization procedures and controls must be implemented to ensure each authenticated entity also has a validated and current authorization. Access control policies include identity-based policies, role-based policies, and attribute-based policies. Access enforcement mechanisms include access control lists, access control matrices, and cryptography. ALGs must use these policies and mechanisms to control access on behalf of the application for which it is acting as intermediary.

Information flow control regulates where information is allowed to travel within a network. The flow of all network traffic must be monitored and controlled so it does not introduce any unacceptable risk to the network infrastructure or data. Information flow control policies and enforcement mechanisms are commonly employed by organizations to control the flow of information between designated sources and destinations (e.g., networks, individuals, devices) within information systems. Examples of information flow control restrictions include keeping export controlled information from being transmitted in the clear to the Internet or blocking information marked as classified but is being transported to an unapproved destination. ALGs enforce approved authorizations by employing security policy and/or rules that restrict information system services, provide packet filtering capability based on header or protocol information and/or message filtering capability based on data content (e.g., implementing key word searches or using document characteristics).

Information flow control regulates where information is allowed to travel within a network and between interconnected networks. Blocking or restricting detected harmful or suspicious communications between interconnected networks enforces approved authorizations for controlling the flow of traffic. This requirement applies to the flow of information between the ALG when used as a gateway or boundary device which allows traffic flow between interconnected networks of differing security policies. The ALG is installed and configured such that it restricts or blocks information flows based on guidance in the PPSM regarding restrictions for boundary crossing for ports, protocols and services. Information flow restrictions may be implemented based on attribute- and content-based inspection of the source, destination, headers, and/or content of the communications traffic. The ALG must be configured with policy filters (e.g., security policy, rules, and/or signatures) that restrict or block information system services; provide a packet-filtering capability based on header information; and/or perform message-filtering based on message content. The policy filters used depends upon the type of application gateway (e.g., web, email, or TLS).

Display of a standardized and approved use notification before granting access to the network ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance. System use notifications are required only for access via logon interfaces with human users and are not required when such human interfaces do not exist. This requirement applies to network elements that have the concept of a user account and have the logon function residing on the network element. The banner must be formatted in accordance with DTM-08-060. Use the following verbiage for network elements that can accommodate banners of 1300 characters: "You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details." Use the following verbiage for operating systems that have severe limitations on the number of characters that can be displayed in the banner: "I've read & consent to terms in IS user agreem't." This policy only applies to ALGs (e.g., identity management or authentication gateways) that provide user account services as part of the intermediary services.

The banner must be acknowledged by the user prior to allowing the user access to the network. This provides assurance that the user has seen the message and accepted the conditions for access. If the consent banner is not acknowledged by the user, DoD will not be in compliance with system use notifications required by law. To establish acceptance of the application usage policy, a click-through banner at application logon is required. The network element must prevent further activity until the user executes a positive action to manifest agreement by clicking on a box indicating "OK". This policy only applies to gateways (e.g., identity management or authentication gateways) that provide user account services as part of the intermediary services.

Display of a standardized and approved use notification before granting access to the publicly accessible network element ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance. System use notifications are required only for access via logon interfaces with human users and are not required when such human interfaces do not exist. This requirement applies to network elements that have the concept of a user account and have the logon function residing on the network element. The banner must be formatted in accordance with DTM-08-060. Use the following verbiage for network elements that can accommodate banners of 1300 characters: "You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details." Use the following verbiage for operating systems that have severe limitations on the number of characters that can be displayed in the banner: "I've read & consent to terms in IS user agreem't." This policy only applies to gateways (e.g., identity management or authentication gateways) that provide user account services as part of the intermediary services off-loaded from the application. Publicly access systems are used in DoD to provide benefit information, pay information, or public services. There may also be self-registration and authorization services provided by these gateways.

Without confidentiality protection mechanisms, unauthorized individuals may gain access to sensitive information via a remote access session. Remote access is access to DoD-nonpublic information systems by an authorized user (or an information system) communicating through an external, non-organization-controlled network. Remote access methods include broadband and wireless connections. Remote access methods include, for example, proxied remote encrypted traffic (e.g., TLS gateways, web content filters, and webmail proxies). Encryption provides a means to secure the remote connection so as to prevent unauthorized access to the data traversing the remote access connection, thereby providing a degree of confidentiality. The encryption strength of the mechanism is selected based on the security categorization of the information. This requirement applies to ALGs providing remote access proxy services as part of its intermediary services (e.g., OWA or TLS gateway).

Private key data is used to prove that the entity presenting a public key certificate is the certificate's rightful owner. Compromise of private key data allows an adversary to impersonate the key holder. Private key data associated with software certificates, including those issued to an ALG, is required to be generated and protected in at least a FIPS 140-2 Level 1 validated cryptographic module.

SP 800-52 provides guidance on using the most secure version and configuration of the TLS/SSL protocol. Using older unauthorized versions or incorrectly configuring protocol negotiation makes the gateway vulnerable to known and unknown attacks which exploit vulnerabilities in this protocol. This requirement applies to TLS gateways (also known as SSL gateways) and is not applicable to VPN devices. Application protocols such as HTTPS and DNSSEC use TLS as the underlying security protocol thus are in scope for this requirement. NIS SP 800-52 provides guidance. SP 800-52 sets TLS version 1.1 as a minimum version, thus all versions of SSL are not allowed (including for client negotiation) either on DoD-only or on public facing servers.

Without cryptographic integrity protections, information can be altered by unauthorized users without detection. Remote access is access to DoD-nonpublic information systems by an authorized user (or an information system) communicating through an external, non-organization-controlled network. Remote access methods include broadband and wireless connections. Remote access methods include, for example, proxied remote encrypted traffic (e.g., TLS gateways, web content filters, and webmail proxies). Cryptographic mechanisms used for protecting the integrity of information include, for example, signed hash functions using asymmetric cryptography enabling distribution of the public key to verify the hash information while maintaining the confidentiality of the secret key used to generate the hash. This requirement applies to ALGs providing remote access proxy services as part of its intermediary services (e.g., OWA or TLS gateway).

It is critical for the appropriate personnel to be aware if a system is at risk of failing to process audit logs as required. Without this notification, the security personnel may be unaware of an impending failure of the audit capability and system operation may be adversely affected. Audit processing failures include software/hardware errors, failures in the audit capturing mechanisms, and audit storage capacity being reached or exceeded. Possible audit processing failures also include the inability of ALG to write to the central audit log. This requirement applies to each audit data storage repository (i.e., distinct information system component where audit records are stored), the centralized audit storage capacity of organizations, (i.e., all audit data storage repositories combined), or both. This does not apply to audit logs generated on behalf of the device itself (management).

Auditing and logging are key components of any security architecture. Logging the actions of specific events provides a means to investigate an attack, recognize resource utilization or capacity thresholds, or to simply identify an improperly configured network element. Thus, it is imperative that the collected log data from the various network elements, as well as the auditing tools, be secured and can only be accessed by authorized personnel. This does not apply to audit logs generated on behalf of the device itself (management).

In order to prevent unauthorized connection of devices, unauthorized transfer of information, or unauthorized tunneling (i.e., embedding of data types within data types); organizations must disable or restrict unused or unnecessary physical and logical ports/protocols on information systems. ALGs are capable of providing a wide variety of functions and services. Some of the functions and services provided by default may not be necessary to support essential organizational operations. DoD continually assesses the ports, protocols, and services that can be used for network communications. Some ports, protocols or services have known exploits or security weaknesses. Network traffic using these ports, protocols, and services must be prohibited or restricted in accordance with DoD policy. The ALG is a key network element for preventing these non-compliant ports, protocols, and services from causing harm to DoD information systems. The network ALG must be configured to prevent or restrict the use of prohibited ports, protocols, and services throughout the network by filtering the network traffic and disallowing or redirecting traffic as necessary. Default and updated policy filters from the vendors will disallow older version of protocols and applications and will address most known non-secure ports, protocols, and/or services. However, sources for further policy filters are the IAVMs and the PPSM requirements.

To assure accountability and prevent unauthenticated access, organizational users must be identified and authenticated to prevent potential misuse and compromise of the system. Organizational users include organizational employees or individuals the organization deems to have equivalent status of employees (e.g., contractors). Organizational users (and any processes acting on behalf of users) must be uniquely identified and authenticated for all accesses except the following. 1) Accesses explicitly identified and documented by the organization. Organizations document specific user actions that can be performed on the information system without identification or authentication. 2) Accesses that occur through authorized use of group authenticators without individual authentication. Organizations may require unique identification of individuals in group accounts (e.g., shared privilege accounts) or for detailed accountability of individual activity. This requirement applies to ALGs that provide user proxy services, including identification and authentication. This service must use the site's directory service (e.g., Active Directory). Directory services must not be installed onto the gateway.

User account and privilege validation must be centralized in order to prevent unauthorized access using changed or revoked privileges. ALGs can implement functions such as traffic filtering, authentication, access, and authorization functions based on computer and user privileges. However, the directory service (e.g., Active Directory or LDAP) must not be installed on the ALG, particularly if the gateway resides on the untrusted zone of the Enclave.

User authentication can be used as part of the policy filtering rule sets. Some URLs or network resources can be restricted to authenticated users only. Users are prompted by the application or browser for credentials. Authentication service may be provided by the ALG as an intermediary for the application; however, the authentication credential must be stored in the site's directory services server. This requirement only applies to components where this is specific to the function of the device or has the concept of an organizational user (e.g., proxy capability). This does not apply to authentication for the purpose of configuring the device itself (i.e., device management).

To assure accountability and prevent unauthenticated access, non-privileged users must utilize multifactor authentication to prevent potential misuse and compromise of the system. Multifactor authentication uses two or more factors to achieve authentication. Factors include: 1) Something you know (e.g., password/PIN), 2) Something you have (e.g., cryptographic, identification device, token), and 3) Something you are (e.g., biometric) Non-privileged accounts are not authorized access to the network element regardless of access method. Network access is any access to an application by a user (or process acting on behalf of a user) where said access is obtained through a network connection. Authenticating with a PKI credential and entering the associated PIN is an example of multifactor authentication. This requirement applies to ALGs that provide user authentication intermediary services.

A replay attack may enable an unauthorized user to gain access to the application. Authentication sessions between the authenticator and the application validating the user credentials must not be vulnerable to a replay attack. An authentication process resists replay attacks if it is impractical to achieve a successful authentication by recording and replaying a previous authentication message. A non-privileged account is any account with the authorizations of a non-privileged user. Privileged roles are organization-defined roles assigned to individuals that allow those individuals to perform certain security-relevant functions that ordinary users are not authorized to perform. Security relevant roles include key management, account management, network and system administration, database administration, and web administration. Techniques used to address this include protocols using nonces (e.g., numbers generated for a specific one time use) or challenges (e.g., TLS). Additional techniques include time-synchronous or challenge-response one-time authenticators. This requirement applies to ALGs that provide user authentication intermediary services.

A certificate's certification path is the path from the end entity certificate to a trusted root certification authority (CA). Certification path validation is necessary for a relying party to make an informed decision regarding acceptance of an end entity certificate. Certification path validation includes checks such as certificate issuer trust, time validity and revocation status for each certificate in the certification path. Revocation status information for CA and subject certificates in a certification path is commonly provided via certificate revocation lists (CRLs) or online certificate status protocol (OCSP) responses.

Authorization for access to any network element requires an approved and assigned individual account identifier. To ensure only the assigned individual is using the account, the account must be bound to a user certificate when PKI-based authentication is implemented. This requirement applies to ALGs that provide user authentication intermediary services (e.g., authentication gateway or TLS gateway). This does not apply to authentication for the purpose of configuring the device itself (device management).

Lack of authentication enables anyone to gain access to the network or possibly a network element that provides opportunity for intruders to compromise resources within the network infrastructure. By identifying and authenticating non-organizational users, their access to network resources can be restricted accordingly. Non-organizational users will be uniquely identified and authenticated for all accesses other than those accesses explicitly identified and documented by the organization when related to the use of anonymous access. Authorization requires an individual account identifier that has been approved, assigned, and configured on an authentication server. Authentication of user identities is accomplished through the use of passwords, tokens, biometrics, or in the case of multifactor authentication, some combination thereof. This control applies to application layer gateways that provide content filtering and proxy services on network segments (e.g., DMZ) that allow access by non-organizational users. This requirement focuses on authentication requests to the proxied application for access to destination resources and policy filtering decisions rather than administrator and management functions.

DoS attacks can take multiple forms but have the common objective of overloading or blocking a network or host to deny or seriously degrade performance. If the network does not provide safeguards against DoS attack, network resources will be unavailable to users. Installation of an ALG at key boundaries in the architecture mitigates the risk of DoS attacks. These attacks can be detected by matching observed communications traffic with patterns of known attacks and monitoring for anomalies in traffic volume/type. The ALG must include protection against DoS attacks that originate from inside the enclave which can affect either internal or external systems. These attacks may use legitimate or rogue endpoints from inside the enclave. These attacks can be simple "floods" of traffic to saturate circuits or devices, malware that consumes CPU and memory on a device or causes it to crash, or a configuration issue that disables or impairs the proper function of a device. For example, an accidental or deliberate misconfiguration of a routing table can misdirect traffic for multiple networks. To comply with this requirement, the ALG must monitor outbound traffic for indications of known and unknown DoS attacks. Audit log capacity management along with techniques which prevent the logging of redundant information during an attack also guard against DoS attacks.

Authenticity protection provides protection against man-in-the-middle attacks/session hijacking and the insertion of false information into sessions. This requirement focuses on communications protection for the application session rather than for the network packet and establishes grounds for confidence at both ends of communications sessions in ongoing identities of other parties and in the validity of information transmitted. Depending on the required degree of confidentiality and integrity, web services/SOA will require the use of mutual authentication (two-way/bidirectional).

Captured sessions can be reused in "replay" attacks. This requirement limits the ability of adversaries from capturing and continuing to employ previously valid session IDs. Session IDs are tokens generated by web applications to uniquely identify an application user's session. Unique session identifiers or IDs are the opposite of sequentially generated session IDs, which can be easily guessed by an attacker. Unique session IDs help to reduce predictability of said identifiers. When a user logs out, or when any other session termination event occurs, the network element must terminate the user session to minimize the potential for an attacker to hijack that particular user session. ALGs act as an intermediary for application; therefore, session control is part of the function provided. This requirement focuses on communications protection at the application session, versus network packet level.

Network elements (depending on function) utilize sessions and session identifiers to control application behavior and user access. If an attacker can guess the session identifier, or can inject or manually insert session information, the valid user's application session can be compromised. Unique session IDs address man-in-the-middle attacks, including session hijacking or insertion of false information into a session. If the attacker is unable to identify or guess the session information related to pending application traffic, they will have more difficulty in hijacking the session or otherwise manipulating valid sessions. This requirement focuses on communications protection for the application session rather than for the network packet.

Failure in a secure state can address safety or security in accordance with the mission needs of the organization. Failure to a secure state helps prevent a loss of confidentiality, integrity, or availability in the event of a failure of the information system or a component of the system. Preserving state information helps to facilitate the restart of the ALG application and a return to the operational mode with less disruption. This requirement applies to a failure of the ALG function rather than the device or operating system as a whole which is addressed in the Network Device Management SRG. Since it is usually not possible to test this capability in a production environment, systems should either be validated in a testing environment or prior to installation. This requirement is usually a function of the design of the IDPS component. Compliance can be verified by acceptance/validation processes or vendor attestation.

Providing too much information in error messages risks compromising the data and security of the application and system. Organizations carefully consider the structure/content of error messages. The required information within error messages will vary based on the protocol and error condition. Information that could be exploited by adversaries includes, for example, ICMP messages that reveal the use of firewalls or access-control lists. The DataPower appliance, by default, will respond to ICMP pings, Info requests, and Address Mask queries. This must be disabled on any interface facing an untrusted network or network with a lower security posture.

Data mining is the analysis of large quantities of data to discover patterns and is used in intelligence gathering. Failure to prevent attacks launched against organizational information from unauthorized data mining may result in the compromise of information. Injection attacks allow an attacker to inject code into a program or query or inject malware onto a computer to execute remote commands that can read or modify a database, or change data on a website. Web applications frequently access databases to store, retrieve, and update information. An attacker can construct inputs that the database will execute. This is most commonly referred to as a code injection attack. This type of attack includes XPath and LDAP injections. Compliance requires the ALG to have the capability to prevent code injections. Examples include a Web Application Firewalls (WAFs) or database application gateways.

Data mining is the analysis of large quantities of data to discover patterns and is used in intelligence gathering. Failure to prevent attacks launched against organizational information from unauthorized data mining may result in the compromise of information. Injection attacks allow an attacker to inject code into a program or query or inject malware onto a computer to execute remote commands that can read or modify a database, or change data on a website. These attacks include buffer overrun, XML, JavaScript, and HTML injections. Compliance requires the ALG to have the capability to prevent code injections. Examples include a Web Application Firewalls (WAFs) or database application gateways.

Data mining is the analysis of large quantities of data to discover patterns and is used in intelligence gathering. Failure to prevent attacks launched against organizational information from unauthorized data mining may result in the compromise of information. SQL injection attacks are the most prevalent attacks against web applications and databases. These attacks inject SQL commands that can read, modify, or compromise the meaning of the original SQL query. An attacker can spoof identity; expose, tamper, destroy, or make existing data unavailable; or gain unauthorized privileges on the database server. Compliance requires the ALG to have the capability to prevent SQL code injections. Examples include a Web Application Firewalls (WAFs) or database application gateways.

Data mining is the analysis of large quantities of data to discover patterns and is used in intelligence gathering. Failure to detect attacks launched against organizational databases may result in the compromise of information. Injection attacks allow an attacker to inject code into a program or query or inject malware onto a computer to execute remote commands that can read or modify a database, or change data on a website. Web applications frequently access databases to store, retrieve, and update information. An attacker can construct inputs that the database will execute. This is most commonly referred to as a code injection attack. This type of attack includes XPath and LDAP injections. ALGs with anomaly detection must be configured to protect against unauthorized code injections. These devices must include rules and anomaly detection algorithms to monitor for atypical database queries or accesses. Examples include a Web Application Firewalls (WAFs) or database application gateways.

Data mining is the analysis of large quantities of data to discover patterns and is used in intelligence gathering. Failure to detect attacks launched against organizational databases may result in the compromise of information. SQL injection attacks are the most prevalent attacks against web applications and databases. These attacks inject SQL commands that can read, modify, or compromise the meaning of the original SQL query. An attacker can spoof identity; expose, tamper, destroy, or make existing data unavailable; or gain unauthorized privileges on the database server. ALGs with anomaly detection must be configured to protect against unauthorized data mining attacks. These devices must include rules and anomaly detection algorithms to monitor for atypical database queries or accesses. Examples include a Web Application Firewalls (WAFs) or database application gateways.

Data mining is the analysis of large quantities of data to discover patterns and is used in intelligence gathering. Failure to detect attacks launched against organizational applications may result in the compromise of information. Injection attacks allow an attacker to inject code into a program or query or inject malware onto a computer to execute remote commands that can read or modify a database, or change data on a website. These attacks include buffer overrun, XML, JavaScript, and HTML injections. ALGs with anomaly detection must be configured to protect against unauthorized code injections. These devices must include rules and anomaly detection algorithms to monitor for atypical database queries or accesses. Examples include a Web Application Firewalls (WAFs) or database application gateways.

Without the capability to select a user session to capture or view, investigations into suspicious or harmful events would be hampered by the volume of information captured. The intent of this requirement is to ensure the capability to select specific sessions to capture is available in order to support general auditing/incident investigation, or to validate suspected misuse by a specific user. Examples of session events that may be captured include, port mirroring, tracking websites visited, and recording information and/or file transfers.

Without the ability to centrally manage the content captured in the audit records, identification, troubleshooting, and correlation of suspicious behavior would be difficult and could lead to a delayed or incomplete analysis of an ongoing attack. The content captured in audit records must be managed from a central location (necessitating automation). Centralized management of audit records and logs provides for efficiency in maintenance and management of records, as well as the backup and archiving of those records. Network components requiring centralized audit log management must have the capability to support centralized management. The DoD requires centralized management of all network component audit record content. This requirement does not apply to audit logs generated on behalf of the device itself (management).

Information stored in one location is vulnerable to accidental or incidental deletion or alteration. Off-loading is a common process in information systems with limited audit storage capacity. This does not apply to audit logs generated on behalf of the device itself (management).

Without a real-time alert, security personnel may be unaware of an impending failure of the audit capability and system operation may be adversely affected. Alerts provide organizations with urgent messages. Real-time alerts provide these messages immediately (i.e., the time from event detection to alert occurs in seconds or less). This does not apply to audit logs generated on behalf of the device itself (management).

If the cached authenticator information is out of date, the validity of the authentication information may be questionable. This requirement applies to all ALGs which may cache user authenticators for use throughout a session. This requirement also applies to ALGs that provide user authentication intermediary services (e.g., authentication gateway or TLS gateway). This does not apply to authentication for the purpose of configuring the device itself (device management).

Without configuring a local cache of revocation data, there is the potential to allow access to users who are no longer authorized (users with revoked certificates). The intent of this requirement is to require support for a secondary certificate validation method using a locally cached revocation data, such as Certificate Revocation List (CRL), in case access to OCSP (required by CCI-000185) is not available. Based on a risk assessment, an alternate mitigation is to configure the system to deny access when revocation data is unavailable. This requirement applies to ALGs that provide user authentication intermediary services (e.g., authentication gateway or TLS gateway). This does not apply to authentication for the purpose of configuring the device itself (device management).

Without conforming to Federal Identity, Credential, and Access Management (FICAM)-issued profiles, the information system may not be interoperable with FICAM-authentication protocols, such as SAML 2.0 and OpenID 2.0. Use of FICAM-issued profiles addresses open identity management standards. This requirement only applies to components where this is specific to the function of the device or has the concept of a non-organizational user, (e.g., ALG capability that is the front end for an application in a DMZ).

Non-DoD approved PKIs have not been evaluated to ensure that they have security controls and identity vetting procedures in place which are sufficient for DoD systems to rely on the identity asserted in the certificate. PKIs lacking sufficient security controls and identity vetting procedures risk being compromised and issuing certificates that enable adversaries to impersonate legitimate users. The authoritative list of DoD-approved PKIs is published at http://iase.disa.mil/pki-pke/interoperability. DoD-approved PKI CAs may include Category I, II, and III certificates. Category I DoD-Approved External PKIs are PIV issuers. Category II DoD-Approved External PKIs are Non-Federal Agency PKIs cross certified with the Federal Bridge Certification Authority (FBCA). Category III DoD-Approved External PKIs are Foreign, Allied, or Coalition Partner PKIs. Deploying the ALG with TLS enabled will require the installation of DoD and/or DoD-Approved CA certificates in the trusted root certificate store of each proxy to be used for TLS traffic. This requirement focuses on communications protection for the application session rather than for the network packet.

If the network does not provide safeguards against DoS attacks, network resources will be unavailable to users. Load balancing provides service redundancy; which service redundancy reduces the susceptibility of the ALG to many DoS attacks. The ALG must be configured to prevent or mitigate the impact on network availability and traffic flow of DoS attacks that have occurred or are ongoing. This requirement applies to the network traffic functionality of the device as it pertains to handling network traffic. Some types of attacks may be specialized to certain network technologies, functions, or services. For each technology, known and potential DoS attacks must be identified and solutions for each type implemented.

If the network does not provide safeguards against DoS attacks, network resources will be unavailable to users. Installation of content filtering gateways and application layer firewalls at key boundaries in the architecture mitigates the risk of DoS attacks. These attacks can be detected by matching observed communications traffic with patterns of known attacks and monitoring for anomalies in traffic volume, type, or protocol usage. Detection components that use signatures can detect known attacks by using known attack signatures. Signatures are usually obtained from and updated by the ALG component vendor. This requirement applies to the communications traffic functionality of the ALG as it pertains to handling communications traffic, rather than to the ALG device itself.

If the network does not provide safeguards against DoS attacks, network resources will be unavailable to users. Installation of content filtering gateways and application layer firewalls at key boundaries in the architecture mitigates the risk of DoS attacks. These attacks can be detected by matching observed communications traffic with patterns of known attacks. Detection components that use pattern recognition pre-processors can detect attacks when signatures for the attack do not exist or are not installed. These attacks include zero-day attacks which are new attacks for which vendors have not yet developed signatures. This requirement applies to the communications traffic functionality of the ALG as it pertains to handling communications traffic, rather than to the ALG device itself.

Unrestricted traffic may contain malicious traffic which poses a threat to an enclave or to other connected networks. Additionally, unrestricted traffic may transit a network, which uses bandwidth and other resources. Access control policies and access control lists implemented on devices that control the flow of network traffic (e.g., application level firewalls and Web content filters), ensure the flow of traffic is only allowed from authorized sources to authorized destinations. Networks with different levels of trust (e.g., the Internet or CDS) must be kept separate.

A common vulnerability of network elements is unpredictable behavior when invalid inputs are received. This requirement guards against adverse or unintended system behavior caused by invalid inputs, where information system responses to the invalid input may be disruptive or cause the system to fail into an unsafe state. The behavior will be derived from the organizational and system requirements and includes, but is not limited to, notification of the appropriate personnel, creating an audit record, and rejecting invalid input. This requirement applies to gateways and firewalls that perform content inspection or have higher-layer proxy functions.

Unauthorized or unapproved network services lack organizational verification or validation and therefore may be unreliable or serve as malicious rogues for valid services. Examples of network services include service-oriented architectures (SOAs), cloud-based services (e.g., infrastructure as a service, platform as a service, or software as a service), cross-domain, Voice Over Internet Protocol, Instant Messaging, auto-execute, and file sharing.

Unauthorized or unapproved network services lack organizational verification or validation and therefore, may be unreliable or serve as malicious rogues for valid services. Automated mechanisms can be used to send automatic alerts or notifications. Such automatic alerts or notifications can be conveyed in a variety of ways (e.g., telephonically, via electronic mail, via text message, or via websites). The ALG must either send the alert to a management console that is actively monitored by authorized personnel or use a messaging capability to send the alert directly to designated personnel.

If inbound communications traffic is not continuously monitored, hostile activity may not be detected and prevented. Output from application and traffic monitoring serves as input to continuous monitoring and incident response programs. Internal monitoring includes the observation of events occurring on the network crosses internal boundaries at managed interfaces such as web content filters. Depending on the type of ALG, organizations can monitor information systems by monitoring audit activities, application access patterns, characteristics of access, content filtering, or unauthorized exporting of information across boundaries. Unusual/unauthorized activities or conditions may include large file transfers, long-time persistent connections, unusual protocols and ports in use, and attempted communications with suspected malicious external addresses.

If outbound communications traffic is not continuously monitored, hostile activity may not be detected and prevented. Output from application and traffic monitoring serves as input to continuous monitoring and incident response programs. Internal monitoring includes the observation of events occurring on the network crosses internal boundaries at managed interfaces such as web content filters. Depending on the type of ALG, organizations can monitor information systems by monitoring audit activities, application access patterns, characteristics of access, content filtering, or unauthorized exporting of information across boundaries. Unusual/unauthorized activities or conditions may include large file transfers, long-time persistent connections, unusual protocols and ports in use, and attempted communications with suspected malicious external addresses.

Without an alert, security personnel may be unaware of major detection incidents that require immediate action and this delay may result in the loss or compromise of information. Since these incidents require immediate action, these messages are assigned a critical or level 1 priority/severity, depending on the system's priority schema. In accordance with CCI-001242, the ALG which provides content inspection services are a real-time intrusion detection system. These systems must generate an alert when detection events from real-time monitoring occur. Alerts may be transmitted, for example, telephonically, by electronic mail messages, or by text messaging. The ALG must either send the alert to a management console that is actively monitored by authorized personnel or use a messaging capability to send the alert directly to designated personnel.

Without an alert, security personnel may be unaware of major detection incidents that require immediate action and this delay may result in the loss or compromise of information. The ALG generates an alert which notifies designated personnel of the Indicators of Compromise (IOCs) which require real-time alerts. These messages should include a severity level indicator or code as an indicator of the criticality of the incident. These indicators reflect the occurrence of a compromise or a potential compromise. Since these incidents require immediate action, these messages are assigned a critical or level 1 priority/severity, depending on the system's priority schema. Alerts may be transmitted, for example, telephonically, by electronic mail messages, or by text messaging. The ALG must either send the alert to a management console that is actively monitored by authorized personnel or use a messaging capability to send the alert directly to designated personnel.

Without an alert, security personnel may be unaware of major detection incidents that require immediate action and this delay may result in the loss or compromise of information. The ALG generates an alert which notifies designated personnel of the Indicators of Compromise (IOCs) which require real-time alerts. These messages should include a severity level indicator or code as an indicator of the criticality of the incident. These indicators reflect the occurrence of a compromise or a potential compromise. Since these incidents require immediate action, these messages are assigned a critical or level 1 priority/severity, depending on the system's priority schema. CJCSM 6510.01B, "Cyber Incident Handling Program", lists nine Cyber Incident and Reportable Event Categories. DoD has determined that categories identified by CJCSM 6510.01B Major Indicators (category 1, 2, 4, or 7 detection events) will require an alert when an event is detected. Alerts may be transmitted, for example, telephonically, by electronic mail messages, or by text messaging. The ALG must either send the alert to a management console that is actively monitored by authorized personnel or use a messaging capability to send the alert directly to designated personnel.

Without an alert, security personnel may be unaware of major detection incidents that require immediate action and this delay may result in the loss or compromise of information. The ALG generates an alert which notifies designated personnel of the Indicators of Compromise (IOCs) which require real-time alerts. These messages should include a severity level indicator or code as an indicator of the criticality of the incident. These indicators reflect the occurrence of a compromise or a potential compromise. Since these incidents require immediate action, these messages are assigned a critical or level 1 priority/severity, depending on the system's priority schema. CJCSM 6510.01B, "Cyber Incident Handling Program", lists nine Cyber Incident and Reportable Event Categories. DoD has determined that categories identified by CJCSM 6510.01B Major Indicators (category 1, 2, 4, or 7 detection events) will require an alert when an event is detected. Alerts may be transmitted, for example, telephonically, by electronic mail messages, or by text messaging. The ALG must either send the alert to a management console that is actively monitored by authorized personnel or use a messaging capability to send the alert directly to designated personnel.

Without an alert, security personnel may be unaware of major detection incidents that require immediate action and this delay may result in the loss or compromise of information. The ALG generates an alert which notifies designated personnel of the Indicators of Compromise (IOCs) which require real-time alerts. These messages should include a severity level indicator or code as an indicator of the criticality of the incident. These indicators reflect the occurrence of a compromise or a potential compromise. Since these incidents require immediate action, these messages are assigned a critical or level 1 priority/severity, depending on the system's priority schema. CJCSM 6510.01B, "Cyber Incident Handling Program", lists nine Cyber Incident and Reportable Event Categories. DoD has determined that categories identified by CJCSM 6510.01B Major Indicators (category 1, 2, 4, or 7 detection events) will require an alert when an event is detected. Alerts may be transmitted, for example, telephonically, by electronic mail messages, or by text messaging. The ALG must either send the alert to a management console that is actively monitored by authorized personnel or use a messaging capability to send the alert directly to designated personnel.

Without an alert, security personnel may be unaware of major detection incidents that require immediate action and this delay may result in the loss or compromise of information. The ALG generates an alert which notifies designated personnel of the Indicators of Compromise (IOCs) which require real-time alerts. These messages should include a severity level indicator or code as an indicator of the criticality of the incident. These indicators reflect the occurrence of a compromise or a potential compromise. Since these incidents require immediate action, these messages are assigned a critical or level 1 priority/severity, depending on the system's priority schema. CJCSM 6510.01B, "Cyber Incident Handling Program", lists nine Cyber Incident and Reportable Event Categories. DoD has determined that categories identified by CJCSM 6510.01B Major Indicators (category 1, 2, 4, or 7 detection events) will require an alert when an event is detected. Alerts may be transmitted, for example, telephonically, by electronic mail messages, or by text messaging. The ALG must either send the alert to a management console that is actively monitored by authorized personnel or use a messaging capability to send the alert directly to designated personnel.

Without the capability to capture, record, and log content related to a user session, investigations into suspicious user activity would be hampered. The intent of this requirement is to ensure the capability to select specific sessions to capture is available in order to support general auditing/incident investigation, or to validate suspected misuse by a specific user. Examples of session events that may be captured include, port mirroring, tracking websites visited, and recording information and/or file transfers.

Invalid user input occurs when a user inserts data or characters into an application's data entry fields and the application is unprepared to process that data. This results in unanticipated application behavior potentially leading to an application or information system compromise. Invalid input is one of the primary methods employed when attempting to compromise an application. Network devices with the functionality to perform application layer inspection may be leveraged to validate data content of network communications. Checking the valid syntax and semantics of information system inputs (e.g., character set, length, numerical range, and acceptable values) verifies that inputs match specified definitions for format and content. Software typically follows well-defined protocols that use structured messages (i.e., commands or queries) to communicate between software modules or system components. Structured messages can contain raw or unstructured data interspersed with metadata or control information. If network elements use attacker-supplied inputs to construct structured messages without properly encoding such messages, then the attacker could insert malicious commands or special characters that can cause the data to be interpreted as control information or metadata. Consequently, the module or component that receives the tainted output will perform the wrong operations or otherwise interpret the data incorrectly. Pre-screening inputs prior to passing to interpreters prevents the content from being unintentionally interpreted as commands. Input validation helps to ensure accurate and correct inputs and prevent attacks such as cross-site scripting and a variety of injection attacks. This requirement applies to gateways and firewalls that perform content inspection or have higher-layer proxy functionality.

Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data. The network element must implement cryptographic modules adhering to the higher standards approved by the federal government since this provides assurance they have been tested and validated. This requirement applies only to ALGs that provide encryption intermediary services (e.g., HTTPS, TLS, or DNSSEC).

Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data. The network element must implement cryptographic modules adhering to the higher standards approved by the federal government since this provides assurance they have been tested and validated. This requirement applies only to ALGs that provide encryption intermediary services (e.g., HTTPS, TLS, or DNSSEC).

Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data. The network element must implement cryptographic modules adhering to the higher standards approved by the federal government since this provides assurance they have been tested and validated. This requirement applies only to ALGs that provide encryption intermediary services (e.g., HTTPS, TLS, or DNSSEC).

Using 0.0.0.0 as a listening address allows all interfaces to receive traffic for the service. This creates an unnecessary exposure when services are configured to listen on this address.