helmetjs content-security-policy-parser up to 0.5.x prototype pollution

Summaryinfo

A vulnerability classified as critical was found in helmetjs content-security-policy-parser up to 0.5.x. The affected element is an unknown function. The manipulation results in prototype pollution. This vulnerability was named CVE-2025-55164. The attack may be performed from remote. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in helmetjs content-security-policy-parser up to 0.5.x. It has been classified as critical. Affected is an unknown function. The manipulation with an unknown input leads to a prototype pollution vulnerability. CWE is classifying the issue as CWE-1321. The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype. This is going to have an impact on integrity, and availability. CVE summarizes:

content-security-policy-parser parses content security policy directives. A prototype pollution vulnerability exists in versions 0.5.0 and earlier, wherein if a policy name is called __proto__, one can override the Object prototype. This issue has been patched in version 0.6.0. A workaround involves disabling prototype method in NodeJS, neutralizing all possible prototype pollution attacks. Provide either --disable-proto=delete (recommended) or --disable-proto=throw as an argument to node to enable this feature.

The advisory is available at github.com. This vulnerability is traded as CVE-2025-55164 since 08/07/2025. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1059 by the MITRE ATT&CK project.

Upgrading to version 0.6.0 eliminates this vulnerability. Applying the patch b13a52554f0168af393e3e38ed4a94e9e6aea9dc is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

• helmetjs

Name

• content-security-policy-parser

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5

License

• open-source

Website

• Product: https://github.com/helmetjs/content-security-policy-parser/

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If you want to get best quality of vulnerability data, you may have to visit VulDB.

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