CVE-2025-0241: Mozilla Firefox · Memory Leak
Affects Mozilla FirefoxSource CVE Database V5
Not known to be exploited · CVSS 7.7 High : upgrade to 134 soon.
Data as of 26 Oct 2026, 11:42 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 54% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 134
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:LExploitation evidence
Disclosed: evidence found.
CVE published 7 Jan 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by 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 134.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Mozilla Firefox | Affected
| Fixed in
|
AI-suggested
An official fix is available and has been released by Mozilla in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6. Users and administrators should update affected products to these versions or later to remediate this vulnerability. No additional mitigation steps are indicated by the vendor advisory.
Description
When segmenting specially crafted text, segmentation would corrupt memory leading to a potentially exploitable crash. This vulnerability was fixed in Firefox 134, Firefox ESR 128.6, Thunderbird 134, and Thunderbird 128.6.
References
- bugzilla.mozilla.org/show_bug.cgi?id=1933023 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-01/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-02/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-04/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-05/ (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/01/msg00004.html (opens in a new tab)