CVE-2026-92055: Mozilla Firefox · Improper Privilege Management
Affects Mozilla FirefoxSource CVE Database V5
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 13% 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 |
|---|---|---|
| Mozilla Firefox | Affected
| Fixed in
|
AI-suggested
A fix is available and has been officially released by Mozilla. Users and administrators should update to Firefox 156, Firefox ESR 153.3, Thunderbird 156, or Thunderbird 153.3 to remediate this vulnerability. No additional mitigation actions are required beyond applying the official update.
Description
CVE-2026-92055 is a high-severity privilege escalation vulnerability in the DevTools component of Mozilla Firefox. This issue allows an attacker to gain elevated privileges within the affected software. The vulnerability has been fixed in Firefox version 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.
References
- bugzilla.mozilla.org/show_bug.cgi?id=2063652 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-90/ (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/mfsa2026-96/ (opens in a new tab)