CVE-2026-92023: Mozjs52 · Use-after-free in the XML component
Affects mozjs52Source GCVE Database
Not known to be exploited · CVSS 8.8 High.
Data as of 31 Oct 2026, 08:20 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 24% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
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 15 Sep 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 30 Oct 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 officially fixed by Mozilla in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3. Users and administrators should apply these updates promptly to remediate the issue. No additional mitigation actions are required beyond applying the official patches.
Description
CVE-2026-92023 is a use-after-free vulnerability in the XML component of the mozjs52 JavaScript engine. This vulnerability has been fixed in Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, and Thunderbird 153.3. The vulnerability has a high impact and a CVSS score of 8.8, indicating it can lead to high confidentiality, integrity, and availability impacts. Multiple specific vulnerable versions are identified, including various Ubuntu package versions. The vendor has released official fixes for this issue.
References
- nvd.nist.gov/vuln/detail/CVE-2026-92023 (opens in a new tab)
- bugzilla.mozilla.org/show_bug.cgi?id=2068342 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-90 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-91 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-92 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-93 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-94 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-95 (opens in a new tab)
- ubuntu.com/security/CVE-2026-92023 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-92023 (opens in a new tab)
- mozilla.org/en-US/security/advisories/mfsa2026-90/ (opens in a new tab)