CVE-2026-4705

Undefined behavior in the WebRTC: Signaling component

State: Published
Severity: 9.8 Critical
Published: Mar 24, 2026
Updated: Apr 13, 2026
Reserved: Mar 23, 2026

Description

Undefined behavior in the WebRTC: Signaling component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.

Scores

CVSS	Score	Vector	Source
3.1	9.8 Critical	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	CISA-ADP

Weaknesses

CWE-758 Reliance on Undefined, Unspecified, or Implementation-Defined Behavior

Affected Products

Product	Versions
FirefoxMozilla	140.9 through 140.*Not affected 149 and laterNot affected
ThunderbirdMozilla	140.9 through 140.*Not affected 149 and laterNot affected

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2014873
https://www.mozilla.org/security/advisories/mfsa2026-20/
https://www.mozilla.org/security/advisories/mfsa2026-22/
https://www.mozilla.org/security/advisories/mfsa2026-23/
https://www.mozilla.org/security/advisories/mfsa2026-24/

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