Firefox <149 Mitigation Bypass in Networking:HTTP Component
CVE-2026-4700 Published on March 24, 2026
Mitigation bypass in the Networking: HTTP component
Mitigation bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 149, Firefox ESR 140.9, Thunderbird 149, and Thunderbird 140.9.
Vulnerability Analysis
CVE-2026-4700 is exploitable with network access, and does not require authorization privileges or 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 critical as this vulnerability has a high impact to the confidentiality, integrity and availability of this component.
Weakness Type
Authentication Bypass Using an Alternate Path or Channel
A product requires authentication, but the product has an alternate path or channel that does not require authentication.
Products Associated with CVE-2026-4700
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Affected Versions
Mozilla Firefox:- Version 140.9, <= 140.* is unaffected.
- Version 149, <= * is unaffected.
- Version 140.9, <= 140.* is unaffected.
- Version 149, <= * 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.