CVE-2026-92017: Mozjs52 · Privilege escalation in the DOM: Service Workers component
Affects mozjs52Source GCVE Database
Not known to be exploited · CVSS 8.8 High.
Data as of 30 Oct 2026, 20:25 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 15% 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
A fix is available and has been officially released by Mozilla. Users and administrators should update to Firefox 156, Firefox ESR 115.41, Firefox ESR 140.16, Firefox ESR 153.3, Thunderbird 156, Thunderbird 140.16, or Thunderbird 153.3 to remediate this vulnerability. Applying these updates will mitigate the risk without requiring additional action.
Description
CVE-2026-92017 is a privilege escalation vulnerability in the DOM Service Workers component of mozjs52. It allows an attacker to escalate privileges within affected Firefox and Thunderbird versions. The 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.
References
- nvd.nist.gov/vuln/detail/CVE-2026-92017 (opens in a new tab)
- bugzilla.mozilla.org/show_bug.cgi?id=2061777 (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)
- 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-2026-92017 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-92017 (opens in a new tab)
- mozilla.org/en-US/security/advisories/mfsa2026-90/ (opens in a new tab)