Mozilla Firefox Security Technical Implementation Guide
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Digest of Updates −2 ✎ 8
Comparison against the immediately-prior release (V4R15). Rule matching uses the Group Vuln ID. Content-change detection compares the rule’s description, check, and fix text after stripping inline markup — cosmetic-only edits aren’t flagged.
Removed rules 2
- V-15990 Medium The Firefox browser home page is not set to blank or a trusted site.
- V-64891 Medium Extensions install must be disabled.
Content changes 8
- V-15776 Medium checkfix FireFox is configured to use a password store with or without a master password.
- V-15777 Medium descriptioncheckfix History retention must be enabled.
- V-15983 Medium descriptioncheckfix Firefox must be configured to allow only TLS.
- V-15986 Medium checkfix Firefox is configured to allow JavaScript to disable or replace context menus.
- V-17988 High check Installed version of Firefox unsupported.
- V-19741 Medium description Firefox application is set to auto-update.
- V-19743 Medium checkfix Firefox required security preferences cannot be changed by user.
- V-6318 Medium descriptioncheckfix The DOD Root Certificate is not installed.
- RMF Control
- IA-5
- Severity
- M
- CCI
- CCI-000185
- Version
- DTBG010
- Vuln IDs
-
- V-6318
- Rule IDs
-
- SV-33373r4_rule
Checks: C-16602r5_chk
Navigate to Tools >> Options >> Advanced >> Certificates tab >> View Certificates button. On the Certificate Manager window, select the "Authorities" tab. Scroll through the Certificate Name list to the U.S. Government heading. Look for the entry for the DoD Root CA 2. If there is an entry for the DoD Root CA 2, select the entry and then the "View" button, and ensure the publishing organization is "US Government." If there is no entry for the DoD Root CA 2, this is a finding. NOTE: In a Windows environment, use of policy setting "security.enterprise_roots.enabled=true" will point Firefox to the Windows CA and is allowed.
Fix: F-5841r2_fix
Install the DOD CA 2 root certificate.
- RMF Control
- SI-4
- Severity
- M
- CCI
- CCI-001274
- Version
- DTBF050
- Vuln IDs
-
- V-15768
- Rule IDs
-
- SV-16707r1_rule
Checks: C-16611r1_chk
Type "about:config" in the browser address bar. Verify Preference Name "security.default_personal_cert" is set to "Ask Every Time" and is locked to prevent the user from altering. Criteria: If the value of "security.default_personal_cert" is set incorrectly or is not locked, then this is a finding.
Fix: F-15985r1_fix
Set the value of "security.default_personal_cert" to "Ask Every Time". Use the Mozilla.cfg file to lock the preference so users cannot change it.
- RMF Control
- SI-3
- Severity
- M
- CCI
- CCI-001242
- Version
- DTBF100
- Vuln IDs
-
- V-15770
- Rule IDs
-
- SV-16709r1_rule
Checks: C-16614r1_chk
Use Method 1 or 2 to check if the following extensions are listed in the browser configuration: HTA, JSE, JS, MOCHA, SHS, VBE, VBS, SCT, WSC. By default, most of these extensions will not show up on the Firefox listing. Criteria: Method 1: In about:plugins, Installed plug-in, inspect the entries in the Suffixes column. If any of the prohibited extensions are found, then for each of them, verify that it is not associated with an application that executes code. However, applications such as Notepad.exe that do not execute code may be associated with the extension. If the extension is associated with an unauthorized application, then this is a finding. If the extension exists but is not associated with an application, then this is a finding. Method 2: Use the Options User Interface Applications menu to search for the prohibited extensions in the Content column of the table. If an extension that is not approved for automatic execution exists and the entry in the Action column is associated with an application that does not execute the code (e.g., Notepad), then do not mark this as a finding. If the entry exists and the "Action" is 'Save File' or 'Always Ask', then this is not a finding. If an extension exists and the entry in the Action column is associated with an application that does/can execute the code, then this is a finding.
Fix: F-15987r1_fix
Remove any unauthorized extensions from the autodownload list.
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF105
- Vuln IDs
-
- V-15771
- Rule IDs
-
- SV-16710r3_rule
Checks: C-16615r2_chk
Procedure: Open a browser window, type "about:config" in the address bar. Criteria: If the value of "network.protocol-handler.external.shell" is not "false" or is not locked, then this is a finding.
Fix: F-15988r3_fix
Procedure: Set the value of "network.protocol-handler.external.shell" to "false" and lock using the Mozilla.cfg file.
- RMF Control
- SI-3
- Severity
- M
- CCI
- CCI-001243
- Version
- DTBF110
- Vuln IDs
-
- V-15772
- Rule IDs
-
- SV-16711r2_rule
Checks: C-16616r2_chk
Open a browser window, type "about:config" in the address bar. Criteria: If the “plugin.disable_full_page_plugin_for_types” value is not set to include the following external extensions and not locked, then this is a finding: PDF, FDF, XFDF, LSL, LSO, LSS, IQY, RQY, XLK, XLS, XLT, POT PPS, PPT, DOS, DOT, WKS, BAT, PS, EPS, WCH, WCM, WB1, WB3, RTF, DOC, MDB, MDE, WBK, WB1, WCH, WCM, AD, ADP.
Fix: F-15989r2_fix
Ensure the following extensions are not automatically opened by Firefox without user confirmation. Do not use plugins and add-ons to open these files. Use the "plugin.disable_full_page_plugin_for_types" preference to set and lock the following extensions so that an external application rather than an add-on or plugin will not be used. (PDF, FDF, XFDF, LSL, LSO, LSS, IQY, RQY, XLK, XLS, XLT, POT PPS, PPT, DOS, DOT, WKS, BAT, PS, EPS, WCH, WCM, WB1, WB3, RTF, DOC, MDB, MDE, WBK, WB1, WCH, WCM, AD, ADP)
- RMF Control
- SC-18
- Severity
- M
- CCI
- CCI-001170
- Version
- DTBF120
- Vuln IDs
-
- V-15773
- Rule IDs
-
- SV-16712r1_rule
Checks: C-16617r1_chk
Open a browser window, type "about:plugins" in the address bar. Criteria: If the Mozilla ActiveX control and plugin support is present and enabled, then this is a finding.
Fix: F-15990r1_fix
Remove/uninstall the Mozilla ActiveX plugin
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF140
- Vuln IDs
-
- V-15774
- Rule IDs
-
- SV-16713r1_rule
Checks: C-16619r1_chk
Type "about:config" in the address bar, verify that the preference name “browser.formfill.enable" is set to “false” and locked. Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, then this is a finding.
Fix: F-15991r1_fix
Ensure the preference “browser.formfill.enable" is set and locked to the value of “False”.
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF150
- Vuln IDs
-
- V-15775
- Rule IDs
-
- SV-16714r1_rule
Checks: C-16620r1_chk
In About:Config, verify that the preference name “signon.prefillForms“ is set to “false” and locked. Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, then this is a finding.
Fix: F-15992r1_fix
Ensure the preference " signon.prefillForms " is set and locked to the value of “False”.
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF160
- Vuln IDs
-
- V-15776
- Rule IDs
-
- SV-16715r2_rule
Checks: C-16621r2_chk
Type "about:config" in the browser window. Verify that the preference name “signon.rememberSignons" is set and locked to “false”. Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, then this is a finding.
Fix: F-15993r2_fix
Ensure the preference “signon.rememberSignons“ is set and locked to the value of “false”.
- RMF Control
- AU-12
- Severity
- M
- CCI
- CCI-000169
- Version
- DTBF170
- Vuln IDs
-
- V-15777
- Rule IDs
-
- SV-16716r4_rule
Checks: C-16622r4_chk
Type "about:config" in the address bar of the browser. Verify that the preference "places.history.enabled" is set to “true”, and locked. If the parameter for the history preference is set incorrectly, this is a finding. If the setting is not locked, this is a finding.
Fix: F-15994r4_fix
Ensure the preference "places.history.enabled" is set and locked to the value of “true”.
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF180
- Vuln IDs
-
- V-15778
- Rule IDs
-
- SV-16717r1_rule
Checks: C-16623r1_chk
In About:Config, verify that the preference name “dom.disable_window_open_feature.status " is set to “true” and locked. Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, then this is a finding.
Fix: F-15995r1_fix
Ensure the preference "dom.disable_window_open_feature.status " is set and locked to the value of “true”.
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF181
- Vuln IDs
-
- V-15779
- Rule IDs
-
- SV-16718r1_rule
Checks: C-16624r1_chk
In About:Config, verify that the preference name “dom.disable_window_move_resize" is set and locked to “true”. Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, then this is a finding.
Fix: F-15996r1_fix
Ensure the preference "dom.disable_window_move_resize" is set and locked to the value of “true”.
- RMF Control
- SC-13
- Severity
- M
- CCI
- CCI-002450
- Version
- DTBF030
- Vuln IDs
-
- V-15983
- Rule IDs
-
- SV-16925r6_rule
Checks: C-16610r6_chk
Open a browser window, type "about:config" in the address bar. Verify Preference Name "security.enable_tls" is set to the value "true" and locked. Verify Preference Name "security.tls.version.min" is set to the value "2" and locked. Verify Preference Name "security.tls.version.max" is set to the value "3" and locked. Criteria: If the parameters are set incorrectly, then this is a finding. If the settings are not locked, then this is a finding.
Fix: F-15984r6_fix
Configure the following parameters using the Mozilla.cfg file: LockPref "security.enable_tls" is set to "true". LockPref "security.tls.version.min" is set to "2". LockPref "security.tls.version.max" is set to "3".
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF182
- Vuln IDs
-
- V-15985
- Rule IDs
-
- SV-16927r1_rule
Checks: C-16625r1_chk
In About:Config, verify that the preference name “dom.disable_window_flip" is set and locked to “true”. Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, then this is a finding.
Fix: F-15997r1_fix
Ensure the preference "dom.disable_window_flip" is set and locked to the value of “true”.
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF183
- Vuln IDs
-
- V-15986
- Rule IDs
-
- SV-16928r2_rule
Checks: C-16626r4_chk
Type "about:config" in the address bar of the browser. Verify that the preferences "dom.event.contextmenu.enabled" is set and locked to "false". Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, this is a finding.
Fix: F-15998r4_fix
Ensure the preferences "dom.event.contextmenu.enabled" is set and locked to "false".
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF184
- Vuln IDs
-
- V-15987
- Rule IDs
-
- SV-16929r1_rule
Checks: C-16627r1_chk
Type "about:config" in the address bar of the browser. Verify that the preference “dom.disable_window_status_change" is set and locked to “true”. Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, then this is a finding.
Fix: F-15999r1_fix
Ensure the preference "dom.disable_window_status_change" is set and locked to the value of “true”.
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF185
- Vuln IDs
-
- V-15988
- Rule IDs
-
- SV-16930r1_rule
Checks: C-16628r1_chk
In About:Config, verify that the preference “dom.disable_window_open_feature.status" is set and locked to “true”. Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, then this is a finding.
Fix: F-16000r1_fix
Ensure the preference "dom.disable_window_open_feature.status" is set and locked to the value of “true”.
- RMF Control
- CM-6
- Severity
- M
- CCI
- CCI-000366
- Version
- DTBF130
- Vuln IDs
-
- V-15989
- Rule IDs
-
- SV-16931r1_rule
Checks: C-16629r1_chk
Type "about:config" in the browser window. Verify that the preference name “security.warn_leaving_secure" is set to “true” and locked. Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, then this is a finding.
Fix: F-16003r1_fix
Ensure the preference “security.warn_leaving_secure" is set to “true” and locked on this setting.
- RMF Control
- SA-22
- Severity
- H
- CCI
- CCI-003376
- Version
- DTBF003
- Vuln IDs
-
- V-17988
- Rule IDs
-
- SV-19509r2_rule
Checks: C-20617r3_chk
Method 1: View the following registry key: HKLM\Software\Mozilla\Mozilla Firefox\CurrentVersion Method 2: Search for the firefox.exe file using the search feature of the operating system. Examine the files properties for the product version (not the file version. For Windows OS, determine the version of the file by examining navigating to Properties/Version/Product Version. Examine for all instances of firefox.exe that are present on the endpoint. Criteria: If the version number of the firefox.exe file is less than 50.1.x (or ESR 45.7.x), this is a finding.
Fix: F-18550r2_fix
Upgrade the version of the browser to an approved version by obtaining software from the vendor or other trusted source.
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF080
- Vuln IDs
-
- V-19741
- Rule IDs
-
- SV-21887r2_rule
Checks: C-24187r2_chk
Type "about:config" in the browser window. Verify that 1. The preference name "app.update.enabled" is set to 'false' and locked or 2. If set to "true" then verify that "app.update.url", "app.update.url.details" and "app.update.url.manual" contain url information that point to a trusted server and is not the default setting. (Default would contain mozilla.com or Mozilla.org). Criteria: If the parameter is set incorrectly, then this is a finding. If this setting is not locked, then this is a finding.
Fix: F-20414r3_fix
Ensure the preference "app.update.enable" is set and locked to the value of “False” or that a trusted server is used.
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF090
- Vuln IDs
-
- V-19742
- Rule IDs
-
- SV-59603r1_rule
Checks: C-24188r1_chk
Type "about:config" in the browser window. Verify the preference “extensions.update.enabled” is set to "false" and locked. Criteria: If the parameter is set incorrectly, then this is a finding. If this setting is not locked, then this is a finding.
Fix: F-20415r2_fix
Set the preference “extensions.update.enabled” value to "false" and lock using the Mozilla.cfg file.
- RMF Control
- CM-6
- Severity
- M
- CCI
- CCI-000366
- Version
- DTBF070
- Vuln IDs
-
- V-19743
- Rule IDs
-
- SV-21889r8_rule
Checks: C-24189r10_chk
Verify that required settings are marked as locked in "about:config". Verify that "mozilla.cfg" file is used to lock required security settings. If settings are enable, and not locked, this is a finding. Sample file: // lockPref("browser.download.dir", "N:"); lockPref("browser.download.downloadDir", "N:"); lockPref("app.update.enabled", false); lockPref("extensions.update.enabled", false); lockPref("browser.shell.checkDefaultBrowser", false); lockPref("browser.search.update", false); lockPref("browser.formfill.enable", false); lockPref("signon.prefillForms", false); lockPref("dom.disable_open_during_load", true); lockPref("dom.disable_window_move_resize", true); lockPref("dom.event.contextmenu.enabled", false); lockPref("dom.disable_window_status_change", true); lockPref("dom.disable_window_flip", true); lockPref("dom.disable_window_open_feature.status", true); lockPref("security.warn_leaving_secure", true); lockPref("security.default_personal_cert", "Ask Every Time"); lockPref("signon.rememberSignons", false); lockPref("xpinstall.whitelist.required", true); lockPref(“network.protocol-handler.external.shell”,false); lockPref("security.tls.version.min" ,"2"); lockPref(“security.tls.version.max", "3"); lockPref("plugin.disable_full_page_plugin_for_types", "application/pdf,application/doc,application/xls,application/bat,application/ppt,application/mdb,application/mde,application/fdf,application/xfdf,application/lsl,application/lso,application/lss,application/iqy,application/rqy,application/xlk,application/pot,application/pps,application/dot,application/wbk,application/ps,application/eps,application/wch,application/wcm,application/wbi,application/wb1,application/wb3,application/rtf,application/wch,application/wcm,application/ad,application/adp,application/xlt, application/dos, application/wks"); lockPref("privacy.item.history", false) Note: Append line into local-settings.js file to include in the Mozilla config file.
Fix: F-22495r7_fix
Ensure the required settings in "about:config" are locked using the "mozilla.cfg" file.
- RMF Control
- CM-7
- Severity
- M
- CCI
- CCI-000381
- Version
- DTBF085
- Vuln IDs
-
- V-19744
- Rule IDs
-
- SV-21890r1_rule
Checks: C-24190r1_chk
Type "about:config" in the browser window. Verify the preference "browser.search.update” is set to "false" and locked. Criteria: If the parameter is set incorrectly, then this is a finding. If the setting is not locked, then this is a finding.
Fix: F-20416r2_fix
Ensure the preference "browser.search.update" is set and locked to the value of “False”.