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medium advisory

WebRTC Signaling Denial-of-Service Vulnerability (CVE-2026-4704)

CVE-2026-4704 is a denial-of-service vulnerability in the WebRTC Signaling component affecting Firefox, Firefox ESR, and Thunderbird, potentially disrupting service availability.

CVE-2026-4704 is a denial-of-service vulnerability residing in the WebRTC Signaling component of Mozilla products. This flaw impacts Firefox versions prior to 149, Firefox ESR versions before 140.9, Thunderbird versions lower than 149, and Thunderbird also prior to version 140.9. Successful exploitation of this vulnerability could lead to a denial-of-service condition, rendering the affected application unavailable. The vulnerability was disclosed on March 24, 2026. Defenders should prioritize…

Detection coverage 2

Detect Crashes Related to WebRTC Signaling

medium

Detects application crashes potentially related to the WebRTC signaling vulnerability.

sigma tactics: availability techniques: T1498 sources: application, windows|linux|macos

Detect High CPU Usage by Firefox After WebRTC Connection

low

This rule detects unusual CPU usage by Firefox or Thunderbird after a WebRTC connection, which could indicate a denial-of-service condition due to CVE-2026-4704.

sigma tactics: availability techniques: T1498 sources: process_stats, windows|linux|macos

Detection queries are kept inside the platform. Get full rules →