CVE-2026-124918: Mozjs52 · Privilege escalation due to incorrect boundary conditions in the Graphics: WebRender
Affects mozjs52Source GCVE Database
Not known to be exploited · CVSS 8.8 High.
Data as of 13 Nov 2026, 22:39 UTC
Thin evidence
One scorer or none| CISA-ADP | CVSS 3.1 | 8.8 |
|---|
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 10 Nov 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 13 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
A fix for this vulnerability is available and has been incorporated in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation steps are specified or required beyond applying the official updates.
Description
CVE-2026-124918 is a high-severity privilege escalation vulnerability in the Graphics: WebRender component of mozjs52. It arises from incorrect boundary conditions that could allow an attacker to escalate privileges. This issue was fixed in Firefox 160, Firefox ESR 153.7, Thunderbird 160, and Thunderbird 153.7.
References
- ubuntu.com/security/CVE-2026-124918 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-124918 (opens in a new tab)
- mozilla.org/en-US/security/advisories/mfsa2026-125/ (opens in a new tab)
- mozilla.org/en-US/security/advisories/mfsa2026-127/ (opens in a new tab)
- mozilla.org/en-US/security/advisories/mfsa2026-129/ (opens in a new tab)
- bugzilla.mozilla.org/show_bug.cgi?id=2058993 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-125/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-127/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-128/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-129/ (opens in a new tab)