Mozjs52: It was possible to interrupt the processing of a RegExp bailout and run additional JavaScript, potentially
Affects mozjs52Source GCVE Database
Not known to be exploited · CVSS 6.5 Medium · fixed in 136.0+build3-0ubuntu0.20.04.1 : update mozjs52 when convenient.
Data as of 28 Oct 2026, 22:28 UTC
- Patch
- Available – fixed in 136.0+build3-0ubuntu0.20.04.1, 1:128.12.0+build1-0ubuntu0.22.04.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 4 Mar 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 the Ubuntu to 136.0+build3-0ubuntu0.20.04.1 (firefox package) or 1:128.12.0+build1-0ubuntu0.22.04.1 (thunderbird package).
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 24.04 LTSmozjs102pkg:deb/ubuntu/mozjs102?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSmozjs115pkg:deb/ubuntu/mozjs115?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSmozjs102pkg:deb/ubuntu/mozjs102?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSmozjs78pkg:deb/ubuntu/mozjs78?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSmozjs91pkg:deb/ubuntu/mozjs91?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSthunderbirdpkg:deb/ubuntu/thunderbird?arch=source&distro=jammyOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
It was possible to interrupt the processing of a RegExp bailout and run additional JavaScript, potentially triggering garbage collection when the engine was not expecting it. This vulnerability was fixed in Firefox 136, Firefox ESR 128.8, Thunderbird 136, and Thunderbird 128.8.
References
- ubuntu.com/security/CVE-2025-1934 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-1934 (opens in a new tab)
- mozilla.org/en-US/security/advisories/mfsa2025-14/ (opens in a new tab)
- mozilla.org/en-US/security/advisories/mfsa2025-16/ (opens in a new tab)
- bugzilla.mozilla.org/show_bug.cgi?id=1942881 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-14/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-16/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-17/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-18/ (opens in a new tab)
- ubuntu.com/security/notices/USN-7334-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7663-1 (opens in a new tab)