CVE-2025-0247

Memory safety bugs fixed in Firefox 134 and Thunderbird 134

State: Published
Severity: 9.8 Critical
Published: Jan 7, 2025
Updated: May 20, 2026
Reserved: Jan 6, 2025

Description

Memory safety bugs present in Firefox 133 and Thunderbird 133. 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 134 and Thunderbird 134.

Scores

CVSS	Score	Vector	Source
3.1	9.8 Critical	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	CISA-ADP

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
FirefoxMozilla	134 and laterNot affected
ThunderbirdMozilla	134 and laterNot affected

References

Memory safety bugs fixed in Firefox 134 and Thunderbird 134
https://www.mozilla.org/security/advisories/mfsa2025-01/
https://www.mozilla.org/security/advisories/mfsa2025-04/

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.