CVE-2026-4704 is a high-severity denial-of-service vulnerability affecting the WebRTC signaling component in Mozilla Firefox. It allows an attacker to cause resource exhaustion leading to a denial-of-service condition. The issue was fixed in Firefox 149 and Firefox ESR 140.9. The vulnerability has no impact on confidentiality or integrity but significantly impacts availability. The vendor advisory explicitly states the fix is included in these versions, and no active exploitation has been reported.

The vulnerability can cause denial-of-service by exhausting resources in the WebRTC signaling component, potentially disrupting normal browser operations and user communications relying on WebRTC. There is no indication of confidentiality or integrity compromise. No known exploits have been observed in the wild.

Users and administrators should update to Firefox 149 or Firefox ESR 140.9 or later to remediate this vulnerability. The vendor advisory confirms that the issue is fixed in these versions. No additional mitigation steps are required beyond applying the official update.