Vulnerability · Published Sep 15, 2026 · Assigned by mozilla

CVE-2026-92055Privilege escalation in the DevTools component

High 8.8

In plain English

A high-severity privilege mismanagement in Firefox from Mozilla. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)8.8High
Exploit odds (30 days)0.2%top 86.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Privilege escalation in the DevTools component. This vulnerability was fixed in Firefox 156, Firefox ESR 153.3, Thunderbird 156, and Thunderbird 153.3.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Debian:14thunderbird1:153.3.0esr-1DEBIAN-CVE-2026-92055
Ubuntu:22.04:LTSmozjs102no fix listedUBUNTU-CVE-2026-92055
Ubuntu:24.04:LTSmozjs102no fix listedUBUNTU-CVE-2026-92055
Ubuntu:24.04:LTSmozjs115no fix listedUBUNTU-CVE-2026-92055
Ubuntu:22.04:LTSmozjs78no fix listedUBUNTU-CVE-2026-92055
Ubuntu:22.04:LTSmozjs91no fix listedUBUNTU-CVE-2026-92055
Ubuntu:22.04:LTSthunderbirdno fix listedUBUNTU-CVE-2026-92055

Affected products (as reported)

VendorProductVersions
Mozilla Firefox see references
Mozilla Thunderbird see references

Weakness: CWE-269 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References