Description
Sandbox escape due to incorrect boundary conditions in the WebRTC: Networking component. This vulnerability was fixed in Firefox 150, Thunderbird 150, Firefox ESR 140.10.1, and Thunderbird 140.10.1.
Affected products
mozilla: firefox; mozilla: thunderbird
References5
- www.mozilla.org/security/advisories/mfsa2026-30/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-33/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-36/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-39/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2029461 Permissions Required
Metrics
- CVSS 3.1
-
9.6
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 18 · as of 13 November 2026
- CWE
- CWE-120
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