Mozilla Firefox up to 143.0.2 JIT code injection

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 143.0.2. It has been rated as critical. Affected by this vulnerability is an unknown functionality of the component JIT. Performing a manipulation results in Remote Code Execution. This vulnerability was named CVE-2025-11153. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical has been found in Mozilla Firefox up to 143.0.2. This affects an unknown function of the component JIT. The manipulation with an unknown input leads to a remote code execution vulnerability. CWE is classifying the issue as CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability affects Firefox < 143.0.3.

It is possible to read the advisory at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2025-11153 since 09/29/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 10/13/2025). The attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 266291 (Mozilla Firefox < 143.0.3), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 143.0.3 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (266291). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Web Browser

Vendor

• Mozilla

Name

• Firefox

Version

• 143.0.0
• 143.0.1
• 143.0.2

License

• open-source

Website

• Vendor: https://www.mozilla.org/
• Product: https://www.mozilla.org/en-US/firefox/

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Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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