CVE-2025-13027: Memory safety bugs fixed in Firefox 145 and Thunderbird 145

Severity: high (CVSS 8.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-11-11 · updated 2026-10-18
Weakness: CWE-119

Description

Memory safety bugs present in Firefox 144 and Thunderbird 144. 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 145 and Thunderbird 145.

Affected products

Mozilla Firefox: before 145.0 — fixed in 145.0

How to fix

Upgrade to a fixed version: Mozilla Firefox 145.0. Check the vendor advisory for mitigations.

References

https://bugzilla.mozilla.org/buglist.cgi?bug_id=1987237%2C1990079%2C1991715%2C1994994
https://www.mozilla.org/security/advisories/mfsa2025-87/
https://www.mozilla.org/security/advisories/mfsa2025-90/

Get alerted when CVE-2025-13027 or the next vulnerability affects your stack