CVE-2025-8040Improper Restriction of Operations within the Bounds of a Memory Buffer in Mozilla Firefox

Severity
8.8HIGHNVD
EPSS
0.1%
top 73.63%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedJul 22
Latest updateFeb 2

Description

Memory safety bugs present in Firefox ESR 140.0, Thunderbird ESR 140.0, Firefox 140 and Thunderbird 140. 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 141, Firefox ESR 140.1, Thunderbird 141, and Thunderbird 140.1.

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitability: 2.8 | Impact: 5.9

Affected Packages3 packages

NVDmozilla/firefox< 140.1+1
NVDmozilla/thunderbird< 140.1+1
Ubuntumozilla/thunderbird< 1:140.7.1+build1-0ubuntu0.22.04.1

🔴Vulnerability Details

3
OSV
CVE-2025-8040: Memory safety bugs present in Firefox ESR 1402025-07-22
GHSA
GHSA-7jcf-w576-jvj3: Memory safety bugs present in Firefox ESR 1402025-07-22
CVEList
Memory safety bugs fixed in Firefox ESR 140.1, Thunderbird ESR 140.1, Firefox 141 and Thunderbird 1412025-07-22

📋Vendor Advisories

7
Ubuntu
Thunderbird vulnerabilities2026-02-02
Red Hat
firefox: thunderbird: Memory safety bugs fixed in Firefox ESR 140.1, Thunderbird ESR 140.1, Firefox 141 and Thunderbird 1412025-07-22
Debian
CVE-2025-8040: firefox - Memory safety bugs present in Firefox ESR 140.0, Thunderbird ESR 140.0, Firefox ...2025
Mozilla
Mozilla Foundation Security Advisory 2025-61: CVE-2025-8040
Mozilla
Mozilla Foundation Security Advisory 2025-56: CVE-2025-8040
CVE-2025-8040 — Mozilla Firefox vulnerability | cvebase