CVE-2026-6766

Incorrect boundary conditions in the Libraries component in NSS

State: Published
Severity: 7.5 High
Published: Apr 21, 2026
Updated: May 26, 2026
Reserved: Apr 21, 2026

Description

Incorrect boundary conditions in the Libraries component in NSS. This vulnerability was fixed in Firefox 150, Firefox ESR 140.10, Thunderbird 150, and Thunderbird 140.10.

Scores

CVSS	Score	Vector	Source
3.1	7.5 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N	CISA-ADP

Weaknesses

CWE-754 Improper Check for Unusual or Exceptional Conditions

Affected Products

Product	Versions
FirefoxMozilla	140.10 through 140.*Not affected 150 and laterNot affected
ThunderbirdMozilla	140.10 through 140.*Not affected 150 and laterNot affected

References

https://bugzilla.mozilla.org/show_bug.cgi?id=2023207
https://www.mozilla.org/security/advisories/mfsa2026-30/
https://www.mozilla.org/security/advisories/mfsa2026-32/
https://www.mozilla.org/security/advisories/mfsa2026-33/
https://www.mozilla.org/security/advisories/mfsa2026-34/

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