CVE-2026-4726

Denial-of-service in the XML component. This vulnerability affects Firefox < 149 and Thunderbird < 149.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=1955311	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2026-20/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2026-23/	Vendor Advisory

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 : 2026-03-25 20:55

NVD link : CVE-2026-4726

Mitre link : CVE-2026-4726

CVE.ORG link : CVE-2026-4726

JSON object : View

Products Affected

mozilla

firefox
thunderbird

CWE

CWE-400

Uncontrolled Resource Consumption

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