Info disclosure in Firefox WebSockets before v153/ESR140.13
CVE-2026-16405 Published on July 21, 2026
Information disclosure in the Networking: WebSockets component
Information disclosure in the Networking: WebSockets component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13.
Vulnerability Analysis
CVE-2026-16405 can be exploited 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 have a high impact on confidentiality, with no impact on integrity and availability.
Weakness Type
What is an Information Disclosure Vulnerability?
The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information.
CVE-2026-16405 has been classified to as an Information Disclosure vulnerability or weakness.
Products Associated with CVE-2026-16405
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Affected Versions
Mozilla Firefox:- Version 140.13, <= 140.* is unaffected.
- Version 153, <= * is unaffected.
- Version 140.13, <= 140.* is unaffected.
- Version 153, <= * is unaffected.