CVE-2026-12309

Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=2038476	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-57/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-58/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-60/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-61/	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:::*
	cpe:2.3:a:mozilla:thunderbird:::::-:::*

History

26 Oct 2026, 13:10

Type	Values Removed	Values Added
Summary		(es) Fallo de seguridad de la memoria corregido en Thunderbird 152. Esta vulnerabilidad fue corregida en Firefox 152, Firefox ESR 140.12, Thunderbird 152 y Thunderbird 140.12.

21 Oct 2026, 14:17

Type	Values Removed	Values Added
Summary	~~(en) Memory safety bug fixed in Firefox 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.~~	(en) Memory safety bug fixed in Thunderbird 152. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.

Information

Published : 2026-06-16 13:16

Updated : 2026-10-26 13:10

NVD link : CVE-2026-12309

Mitre link : CVE-2026-12309

CVE.ORG link : CVE-2026-12309

JSON object : View

Products Affected

mozilla

firefox
thunderbird

CWE

CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer

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