Mozilla Firefox up to 143 on Windows Copy as cURL escape output

Summaryinfo

A vulnerability identified as problematic has been detected in Mozilla Firefox up to 143 on Windows. The impacted element is an unknown function of the component Copy as cURL Handler. This manipulation causes Remote Code Execution. This vulnerability is registered as CVE-2025-11713. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability has been found in Mozilla Firefox up to 143 on Windows and classified as problematic. Affected by this vulnerability is some unknown functionality of the component Copy as cURL Handler. The manipulation with an unknown input leads to a remote code execution vulnerability. The CWE definition for the vulnerability is CWE-116. The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Insufficient escaping in the “Copy as cURL” feature could have been used to trick a user into executing unexpected code on Windows. This did not affect the application when running on other operating systems. This vulnerability affects Firefox < 144, Firefox ESR < 140.4, Thunderbird < 144, and Thunderbird < 140.4.

The advisory is shared at bugzilla.mozilla.org. This vulnerability is known as CVE-2025-11713 since 10/13/2025. The exploitation appears to be difficult. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 11/16/2025).

The vulnerability scanner Nessus provides a plugin with the ID 271429 (openSUSE 15 Security Update : MozillaFirefox (SUSE-SU-2025:3775-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 144 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (271429), EUVD (EUVD-2025-34201) and CERT Bund (WID-SEC-2025-2275). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• RESF Rocky Linux
• IGEL OS
• Mozilla Firefox
• Mozilla Firefox ESR
• Mozilla Thunderbird

Productinfo

Type

• Web Browser

Vendor

• Mozilla

Name

• Firefox

Version

• 143

License

• open-source

Website

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

CPE 2.3info

• 🔒

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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