CVE-2025-1011: WebAssembly code generation · Bug
Source GCVE Database
Not known to be exploited · CVSS 9.8 Critical · fixed in 135 : patch affected systems as a priority.
Data as of 30 Oct 2026, 01:09 UTC
- Patch
- Available – fixed in 135, 128.7
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 4 Feb 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 29 Oct 2026.
What to do
AI-suggested
Users and administrators should update affected products to Firefox 135, Firefox ESR 128.7, Thunderbird 135, or Thunderbird 128.7 or later, where this vulnerability has been fixed. No additional mitigation is required once the update is applied.
Description
CVE-2025-1011 is a vulnerability in the WebAssembly code generation component of Mozilla Firefox and Thunderbird that could cause a crash. It may have been possible for an attacker to leverage this flaw to achieve code execution. This issue affects Firefox versions prior to 135, Firefox ESR versions prior to 128.7, Thunderbird versions prior to 128.7, and Thunderbird versions prior to 135. The vulnerability has been fixed in Firefox 135 and Firefox ESR 128.7.
References
- nvd.nist.gov/vuln/detail/CVE-2025-1011 (opens in a new tab)
- bugzilla.mozilla.org/show_bug.cgi?id=1936454 (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/02/msg00005.html (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/02/msg00006.html (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-07 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-09 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-10 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-11 (opens in a new tab)