CVE-2026-6766

  1. OpenCVE
  2. Vulnerabilities (CVE)
  3. CVE-2026-6766
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.

7.5 /10

CVSS v3 : HIGH

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References
Link Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2023207 Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-30/ Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-32/ Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-33/ Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-34/ Vendor Advisory
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*
History

22 Apr 2026, 14:57

Type Values Removed Values Added
References () https://bugzilla.mozilla.org/show_bug.cgi?id=2023207 - () https://bugzilla.mozilla.org/show_bug.cgi?id=2023207 - Permissions Required
References () https://www.mozilla.org/security/advisories/mfsa2026-30/ - () https://www.mozilla.org/security/advisories/mfsa2026-30/ - Vendor Advisory
References () https://www.mozilla.org/security/advisories/mfsa2026-32/ - () https://www.mozilla.org/security/advisories/mfsa2026-32/ - Vendor Advisory
References () https://www.mozilla.org/security/advisories/mfsa2026-33/ - () https://www.mozilla.org/security/advisories/mfsa2026-33/ - Vendor Advisory
References () https://www.mozilla.org/security/advisories/mfsa2026-34/ - () https://www.mozilla.org/security/advisories/mfsa2026-34/ - Vendor Advisory
First Time Mozilla
Mozilla firefox
Mozilla thunderbird
CPE cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*
cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*
cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*

22 Apr 2026, 00:16

Type Values Removed Values Added
References
  • () https://www.mozilla.org/security/advisories/mfsa2026-33/ -
  • () https://www.mozilla.org/security/advisories/mfsa2026-34/ -
Summary (en) Incorrect boundary conditions in the Libraries component in NSS. This vulnerability was fixed in Firefox 150 and Firefox ESR 140.10. (en) 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.

21 Apr 2026, 17:16

Type Values Removed Values Added
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 7.5
CWE CWE-754

21 Apr 2026, 13:16

Type Values Removed Values Added
New CVE
Information

Published : 2026-04-21 13:16

Updated : 2026-04-22 14:57

NVD link : CVE-2026-6766

Mitre link : CVE-2026-6766

CVE.ORG link : CVE-2026-6766

JSON object : View

Products Affected

mozilla

  • firefox
  • thunderbird
CWE
CWE-754

Improper Check for Unusual or Exceptional Conditions