Firefox 152/140.12 Process Sandboxing Disclosure & Sandbox Escape
CVE-2026-12311 Published on June 16, 2026
Information disclosure, sandbox escape in the Security: Process Sandboxing component
Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 152, Firefox ESR 140.12, Thunderbird 152, and Thunderbird 140.12.
Vulnerability Analysis
CVE-2026-12311 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 have a small impact on confidentiality, a small impact on integrity and availability.
Weakness Types
Function Call With Incorrect Variable or Reference as Argument
The software calls a function, procedure, or routine, but the caller specifies the wrong variable or reference as one of the arguments, which may lead to undefined behavior and resultant weaknesses.
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-2026-12311 has been classified to as an Information Disclosure vulnerability or weakness.
Products Associated with CVE-2026-12311
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Affected Versions
Mozilla Firefox:- Version 140.12, <= 140.* is unaffected.
- Version 152, <= * is unaffected.
- Version 140.12, <= 140.* is unaffected.
- Version 152, <= * 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.