CVE-2026-84144

Internally found bugs present in Thunderbird 154 and Thunderbird ESR 153.1. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.6 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/buglist.cgi?bug_id=2054619%2C2054620%2C2054624%2C2054702%2C2054726%2C2054775%2C2055703%2C2058006%2C2058013%2C2058098%2C2058627%2C2058661%2C2059127%2C2059128%2C2059180%2C2059199%2C2059205%2C2061320%2C2061430%2C2061495%2C2061505%2C2061532%2C2061799	Broken Link
https://bugzilla.mozilla.org/buglist.cgi?bug_id=2054625%2C2059002%2C2061775	Broken Link
https://bugzilla.mozilla.org/buglist.cgi?bug_id=2054691%2C2058085%2C2059144%2C2059191%2C2059192%2C2061521%2C2062395%2C2062404	Broken Link
https://www.mozilla.org/security/advisories/mfsa2026-82/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-85/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-86/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-88/	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mozilla:firefox::::::::
	cpe:2.3:a:mozilla:firefox::::::::
	cpe:2.3:a:mozilla:thunderbird::::::::
	cpe:2.3:a:mozilla:thunderbird::::::::

History

No history.

Information

Published : 2026-09-01 13:20

Updated : 2026-09-03 16:33

NVD link : CVE-2026-84144

Mitre link : CVE-2026-84144

CVE.ORG link : CVE-2026-84144

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer

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