CVE-2025-4091CWE-119

CVE-2025-4091

High · published April 29, 2025

CVSS v3.1

8.1

EPSS

Percentile

41.8

In the wild

Unconfirmed

What it is

Memory safety bugs present in Firefox 137, Thunderbird 137, Firefox ESR 128.9, and Thunderbird 128.9. 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 138, Firefox ESR 128.10, Thunderbird 138, and Thunderbird 128.10.

The record

Technical detail

CVSS v3.1: 8.1 · HIGH
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0: Not supplied
EPSS: 0.00498 · 41.8th percentile
Weakness: CWE-119 · Improper Restriction of Operations within the Bounds of a Memory Buffer
Published: 2025-04-29T18:15Z

Affected products (4)

Product	Versions	Fixed in
mozilla/firefox	< 128.10	128.10
mozilla/firefox	< 138.0	138.0
mozilla/thunderbird	< 128.10.0	128.10.0
mozilla/thunderbird	< 138.0	138.0

References (6)

https://bugzilla.mozilla.org/buglist.cgi?bug_id=1951161%2C1952105 · [email protected]https://www.mozilla.org/security/advisories/mfsa2025-28/ · [email protected]https://www.mozilla.org/security/advisories/mfsa2025-29/ · [email protected]https://www.mozilla.org/security/advisories/mfsa2025-31/ · [email protected]https://www.mozilla.org/security/advisories/mfsa2025-32/ · [email protected]https://lists.debian.org/debian-lts-announce/2025/05/msg00024.html · af854a3a-2127-422b-91ae-364da2661108

EPSS history

Timeline

29 APR 13:13Z
Memory safety bugs fixed in Firefox 138, Thunderbird 138, Firefox ESR 128.10, and Thunderbird 128.10
cvelistv5