CVE-2026-5735

Memory safety bugs present in Firefox 149.0.1 and Thunderbird 149.0.1. 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 149.0.2 and Thunderbird 149.0.2.

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=2025475%2C2025477	Broken Link Issue Tracking
https://www.mozilla.org/security/advisories/mfsa2026-25/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-28/
https://access.redhat.com/security/cve/CVE-2026-5735
https://bugzilla.redhat.com/show_bug.cgi?id=2455904
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-5735.json

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-04-07 13:16

Updated : 2026-07-15 01:16

NVD link : CVE-2026-5735

Mitre link : CVE-2026-5735

CVE.ORG link : CVE-2026-5735

JSON object : View

Products Affected

mozilla

thunderbird
firefox

CWE

CWE-787

Out-of-bounds Write

CWE-125

Out-of-bounds Read

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