GitHub Advisoryadvisory · npm
GHSA-9965-vmph-33xx validator.js has a URL validation bypass vulnerability in its isURL function
MEDIUM
Official page ↗
- Aliases
- CVE-2025-56200
- Ecosystem
- npm
- Packages
- validator
- Severity
- Moderate
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- Weaknesses
- CWE-79
- Reviewed
- 2025-10-13
Affected packages
• npm validator: < 13.15.20 → fixed in 13.15.20
Description
A URL validation bypass vulnerability exists in validator.js prior to version 13.15.20. The isURL() function uses '://' as a delimiter to parse protocols, while browsers use ':' as the delimiter. This parsing difference allows attackers to bypass protocol and domain validation by crafting URLs leading to XSS and Open Redirect attacks.
Related
Alias · CVE (1)
- CVE-2025-56200 A URL validation bypass vulnerability exists in validator.js through version 13.15.15. vulnerability
Weakness · CWE (1)
- CWE-79 Improper Neutralization of Input During Web Page Generation weakness
References
- https://nvd.nist.gov/vuln/detail/CVE-2025-56200 advisory
- https://github.com/validatorjs/validator.js/issues/2600 web
- https://github.com/validatorjs/validator.js/pull/2608 web
- https://github.com/validatorjs/validator.js/commit/cbef5088f02d36caf978f378bb845fe49bdc0809 web
- https://gist.github.com/junan-98/27ae092aa40e2a057d41a0f95148f666 web
- https://gist.github.com/junan-98/a93130505b258b9e4ec9f393e7533596 web
- https://github.com/validatorjs/validator.js package
- https://github.com/validatorjs/validator.js/releases/tag/13.15.20 web
- http://validatorjs.com web