Title

Firefox must be configured to ask which certificate to present to a website when a certificate is required. (Cat II impact)

Discussion

When a website asks for a certificate for user authentication, Firefox must be configured to have the user choose which certificate to present. Websites within DoD require user authentication for access, which increases security for DoD information. Access will be denied to the user if certificate management is not configured.

Check Content

Type "about:policies" in the browser address bar. If "security.default_personal_cert" is not displayed with a value of "Ask Every Time", this is a finding.

Fix Text

Windows group policy: 1. Open the group policy editor tool with "gpedit.msc". 2. Navigate to Policy Path: Computer Configuration\Administrative Templates\Mozilla\Firefox\ Policy Name: Preferences Policy State: Enabled Policy Value: { "security.default_personal_cert": { "Value": "Ask Every Time", "Status": "locked" } } macOS "plist" file: Add the following: <key>Preferences</key> <dict> <key>security.default_personal_cert</key> <dict> <key>Value</key> <string>Ask Every Time</string> <key>Status</key> <string>locked</string> </dict> </dict> Linux "policies.json" file: Add the following in the policies section: "Preferences": { "security.default_personal_cert": { "Value": "Ask Every Time", "Status": "locked" } }

Additional Identifiers

Rule ID: SV-251547r879614_rule

Vulnerability ID: V-251547

Group Title: SRG-APP-000177

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.