Description
Incorrect boundary conditions, integer overflow in the Libraries component in NSS. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
Affected products
mozilla: firefox; mozilla: thunderbird
References4
- www.mozilla.org/security/advisories/mfsa2026-68/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-71/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2043887 Permissions Required
- lists.debian.org/debian-lts-announce/2026/08/msg00019.html
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 48 · as of 14 November 2026
- CWE
- CWE-190
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