CVE-2025-55164
content-security-policy-parser Prototype Pollution Vulnerability May Lead to RCE
- State
- Published
- Severity
- 8.8 High
- Published
- Aug 12, 2025
- Updated
- Aug 20, 2025
- Reserved
- Aug 7, 2025
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 8.8 High | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N | GitHub_M |
Weaknesses
- CWE-1321 Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
Affected Products
| Product | Versions |
|---|---|
content-security-policy-parserhelmetjs |
|
References
- https://github.com/helmetjs/content-security-policy-parser/security/advisories/GHSA-w2cq-g8g3-gm83
- https://github.com/helmetjs/content-security-policy-parser/issues/11
- https://github.com/helmetjs/content-security-policy-parser/commit/b13a52554f0168af393e3e38ed4a94e9e6aea9dc
- https://www.vicarius.io/vsociety/posts/cve-2025-55164-detect-node-csp-parser-vulnerability
- https://www.vicarius.io/vsociety/posts/cve-2025-55164-mitigate-csp-parser-vulnerability
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