Description
Cookie storage for non-HTML temporary documents was being shared incorrectly with normal browsing content, allowing information from private tabs to escape Incognito mode even after the user closed all tabs. This vulnerability was fixed in Firefox for iOS 143.1.
Affected products
mozilla: firefox
References2
- www.mozilla.org/security/advisories/mfsa2025-79/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1684624 Issue TrackingPermissions Required
Metrics
- CVSS 3.1
-
4.0
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 2 · as of 9 November 2026
- CWE
- CWE-359
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