CVE-2026-0891High· 8.1▾ TwilightMemory safety bugs present in Firefox ESR 140.6, Thunderbird ESR 140.6, Firefox 146 and Thunderbird 146. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploit…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 44.6 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Jul 4.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.4%
0.4% → 0.5%
Memory safety bugs present in Firefox ESR 140.6, Thunderbird ESR 140.6, Firefox 146 and Thunderbird 146. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.
firefox < 140.7.0firefox < 147.0thunderbird < 140.7.0thunderbird < 147.0Upgrade past the affected range:
firefox 147.0thunderbird 147.0Connected by shared product, vendor, weakness, or advisory.
CVE-2026-0879Critical· 9.8Sandbox escape due to incorrect boundary conditions in the Graphics component
CVE-2026-0878High· 8.0Sandbox escape due to incorrect boundary conditions in the Graphics: CanvasWebGL component
CVE-2026-0882High· 8.8Use-after-free in the IPC component
CVE-2026-0880High· 8.8Sandbox escape due to integer overflow in the Graphics component
CVE-2026-0877High· 8.1Mitigation bypass in the DOM: Security component
CVE-2026-0881Critical· 10.0Sandbox escape in the Messaging System component