Description
JIT miscompilation in the JavaScript Engine component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.
Affected products
mozilla: firefox; mozilla: thunderbird
References3
- www.mozilla.org/security/advisories/mfsa2026-101/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-97/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2073268 Permissions Required
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 19 · as of 10 November 2026
- CWE
- CWE-843
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