Privilege escalation in the Networking component. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.
Fix
Patch, vendor advisory and mitigation references on NVD 4
- https://www.mozilla.org/security/advisories/mfsa2026-30/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-32/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-33/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-34/ Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 8.8 · mozillaNVD modified 2026-10-26 22:10
Affected (CPE criteria) 3
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*
References 5
- https://bugzilla.mozilla.org/show_bug.cgi?id=2017857 Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2026-30/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-32/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-33/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-34/ Vendor Advisory