History retention must be set to 40 days.

From Mozilla Firefox Security Technical Implementation Guide

Part of DTBF170 - FireFox Preferences History

SV-16716r3_rule History retention must be set to 40 days.

Vulnerability discussion

This setting specifies the number of days that Firefox keeps track of the pages viewed in the History List. If you enable this policy setting, a user cannot set the number of days that Firefox keeps track of the pages viewed in the History List. The number of days that Firefox keeps track of the pages viewed in the History List must be specified. If you disable or do not configure this policy setting, a user can set the number of days that Firefox tracks views of pages in the History List.

Check content

Type "about:config" in the address bar of the browser. Verify that the preference “browser.history_expire_days_min" is set to “40”, 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 text

Ensure the preference "browser.history_expire_days_min" is set and locked to the value of “40”.

Pro Tips

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