Mozilla Firefox up to 138 on Windows Copy as cURL command injection

Summaryinfo

A vulnerability was found in Mozilla Firefox up to 138 on Windows. It has been classified as problematic. The affected element is an unknown function of the component Copy as cURL Handler. Performing a manipulation results in Remote Code Execution. This vulnerability is identified as CVE-2025-5265. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Mozilla Firefox up to 138 on Windows. It has been classified as problematic. This affects an unknown code block of the component Copy as cURL Handler. The manipulation with an unknown input leads to a remote code execution vulnerability. CWE is classifying the issue as CWE-77. The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Due to insufficient escaping of the ampersand character in the “Copy as cURL” feature, an attacker could trick a user into using this command, potentially leading to local code execution on the user's system. *This bug only affects Firefox for Windows. Other versions of Firefox are unaffected.* This vulnerability affects Firefox < 139, Firefox ESR < 115.24, and Firefox ESR < 128.11.

It is possible to read the advisory at bugzilla.mozilla.org. This vulnerability is uniquely identified as CVE-2025-5265 since 05/27/2025. The exploitability is told to be difficult. 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 08/17/2025). The attack technique deployed by this issue is T1202 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 237301 (Mozilla Firefox ESR < 115.24), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 139 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (237301) and CERT Bund (WID-SEC-2025-1850). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

• Xerox FreeFlow Print Server

Productinfo

Type

• Web Browser

Vendor

• Mozilla

Name

• Firefox

Version

• 138

License

• open-source

Website

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

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• 🔍

CPE 2.2info

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

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