CVE-2026-117874: Mozjs52 · Use-after-free in the Internationalization component
Affects mozjs52Source GCVE Database
Not known to be exploited · CVSS 6.3 Medium.
Data as of 6 Nov 2026, 05:33 UTC
Thin evidence
One scorer or none| CISA-ADP | CVSS 3.1 | 6.3 |
|---|
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:LExploitation evidence
Disclosed: evidence found.
CVE published 27 Oct 2026
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 5 Nov 2026.
What to do
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.
AI-suggested
This vulnerability has been fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6. Users and administrators should apply these updates to remediate the issue. No additional mitigation steps are required beyond applying the official patches.
Description
CVE-2026-117874 is a use-after-free vulnerability in the Internationalization component of mozjs52. This flaw was addressed and fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6. The vulnerability has a CVSS score of 6.3, indicating a medium severity level. Exploitation requires user interaction but no privileges, and it can impact confidentiality, integrity, and availability. There are no known exploits in the wild at this time.
References
- ubuntu.com/security/CVE-2026-117874 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-117874 (opens in a new tab)
- mozilla.org/en-US/security/advisories/mfsa2026-118/ (opens in a new tab)
- mozilla.org/en-US/security/advisories/mfsa2026-120/ (opens in a new tab)
- mozilla.org/en-US/security/advisories/mfsa2026-122/ (opens in a new tab)
- bugzilla.mozilla.org/show_bug.cgi?id=2073685 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-118/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-119/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-120/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-121/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-122/ (opens in a new tab)