CVE-2026-74936Critical· 9.8▾ AbyssalPoC availableUse-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
▾ Abyssal zone — Critical with a public exploit or in-the-wild use
impact 53.9 · likelihood 0.1 · exploitation 12
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Public exploit / PoC code seen in 1 source. Availability, not in-the-wild use.
Exploit-prediction probability, daily snapshots since Aug 22.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.4%
1 GitHub repo
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
firefox < 140.14.0firefox >= 141.0.0, < 153.1.0thunderbird < 140.14.0thunderbird >= 141.0, < 153.1.0Upgrade past the affected range:
firefox 153.1.0thunderbird 153.1.0Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-74943Critical· 9.8Use-after-free in the Graphics: ImageLib component
CVE-2026-74944Critical· 9.8Use-after-free in the DOM: Core & HTML component
CVE-2026-74940Critical· 9.8Use-after-free in the Graphics: Text component
CVE-2026-74961Critical· 9.1Side-channel in the Web Audio component
CVE-2026-74983High· 8.1Mitigation bypass in the Data Loss Prevention component
CVE-2026-92005Medium· 5.3Use-after-free in the Audio/Video: Web Codecs component