CVE-2026-4729

Memory safety bugs present in Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 149 and Thunderbird 149.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1944033%2C1997282%2C2009213%2C2011412%2C2021925%2C2022034	Broken Link
https://www.mozilla.org/security/advisories/mfsa2026-20/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-23/	Vendor Advisory
https://access.redhat.com/security/cve/CVE-2026-4729
https://bugzilla.redhat.com/show_bug.cgi?id=2450745
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-4729.json

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-03-24 13:16

Updated : 2026-07-15 02:22

NVD link : CVE-2026-4729

Mitre link : CVE-2026-4729

CVE.ORG link : CVE-2026-4729

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CWE-825

Expired Pointer Dereference

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