Skip to main content
VulnerabilityPublished Updated

CVE-2025-11719: Mozilla Firefox · Use After Free

Affects Mozilla FirefoxSource CVE Database V5

0

Not known to be exploited · CVSS 9.8 Critical : upgrade to 144 as a priority.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score
9.8Critical
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.3% chance of exploitation in 30 days – higher than 28% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in 144
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 14 Oct 2025

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq Mirage: no evidence on record.

    No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

What to do

Upgrade Mozilla Firefox to 144.

Affected software

ProductAffectedFixed in
Mozilla FirefoxAffected
  • <144
Fixed in
  • 144

AI-suggested

Mozilla has released official fixes for this vulnerability in Firefox 144 and Thunderbird 144. Users and administrators should update affected products to version 144 or later to remediate this issue. Since the vulnerability is patched, no additional mitigation steps are required beyond applying the official updates.

Description

Starting in Thunderbird 143, the use of the native messaging API by web extensions on Windows could lead to crashes caused by use-after-free memory corruption. This vulnerability was fixed in Firefox 144 and Thunderbird 144.

References

Community reviews

Loading reviews…