CVE-2026-16377
CRITICAL severity · CVSS 9.8 · CWE-693
9.8CVSS CRITICAL
Summary
Mitigation bypass in the PDF Viewer component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
Impact & exploitability
Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactHigh
Integrity impactHigh
Availability impactHigh
Exploit probability (EPSS)1%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products we track (2)
Recommendation
Apply the vendor fix promptly. Open any affected product above for its exact safe version.
Additional information
- NVD record
- https://www.mozilla.org/security/advisories/mfsa2026-68/Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-70/Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-71/Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-72/Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=2037770