Firefox Workers DOM Privilege Escalation (Pre151)
CVE-2026-8955 Published on May 19, 2026
Privilege escalation in the DOM: Workers component
Privilege escalation in the DOM: Workers component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Vulnerability Analysis
CVE-2026-8955 can be exploited with network access, requires user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be very high.
Weakness Type
Improper Privilege Management
The software does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.
Products Associated with CVE-2026-8955
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Affected Versions
Mozilla Firefox:- Version 140.11, <= 140.* is unaffected.
- Version 151, <= * is unaffected.
- Version 140.11, <= 140.* is unaffected.
- Version 151, <= * is unaffected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.