CVE-2025-4091High· 8.1▾ TwilightMemory safety bugs present in Firefox 137, Thunderbird 137, Firefox ESR 128.9, and Thunderbird 128.9. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited …
▾ 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 Sep 30.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.5%
Last analysed / modified upstream
Memory safety bugs present in Firefox 137, Thunderbird 137, Firefox ESR 128.9, and Thunderbird 128.9. 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 138, Firefox ESR 128.10, Thunderbird 138, and Thunderbird 128.10.
firefox < 128.10firefox < 138.0thunderbird < 128.10.0thunderbird < 138.0Upgrade past the affected range:
firefox 138.0thunderbird 138.0Connected by shared product, vendor, weakness, or advisory.
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