CVE-2026-74949
An attacker can exploit multiple vulnerabilities in Mozilla Firefox, Firefox ESR and Thunderbird to elevate privileges, bypass security measures, disclose confidential information, perform spoofing or clickjacking attacks, or cause denial-of-service conditions.
CSIRTS triage
- What
- Multiple vulnerabilities allow attackers to elevate privileges, bypass security measures, disclose information, perform spoofing or clickjacking, or cause denial-of-service.
- Who is affected
- All users of Firefox, Firefox ESR, and Thunderbird.
- Urgency
- High severity requires prompt patching; currently not known to be exploited in the wild.
- Action
- Update to the latest patched version of Firefox, Firefox ESR, or Thunderbird.
AI-assisted analysis generated from the source advisory — verify against the original.
⚡ Watch CVE-2026-74949
Get an email if CVE-2026-74949 is added to CISA KEV, gains public exploit code, or a new advisory cites it — max one per day, one-click unsubscribe.
Exploitation outlook
- Low exploitation risk0.33% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 26% of all EPSS-scored CVEs.
Advisory coverage (5)
- high[NEW] [high] Mozilla Firefox, Firefox ESR and Thunderbird: Multiple Vulnerabilitiescert-bund · 2026-08-19
- unknownMozilla Products Multiple Vulnerabilitieshkcert · 2026-08-19
- unknownDSA-6451-1 firefox-esr - security updatedebian · 2026-08-19
- unknownMultiple vulnerabilities in Mozilla products (August 19, 2026)cert-fr-avis · 2026-08-19
- highCVE-2026-74949: Privilege escalation due to use-after-free in the Graphics: Canvas2D component. This vulnerabi…nvd · 2026-08-18
External references
Embed the live status
— this badge updates automatically when the KEV or exploit status changes. How to embed it →
[](https://www.csirts.com/cve/CVE-2026-74949)