Vulnerability Description
Astro is a web framework. Versions 5.15.7 and below have a double URL encoding bypass which allows any unauthenticated attacker to bypass path-based authentication checks in Astro middleware, granting unauthorized access to protected routes. While the original CVE-2025-64765 was fixed in v5.15.8, the fix is insufficient as it only decodes once. By using double-encoded URLs, attackers can still bypass authentication and access any route protected by middleware pathname checks. This issue is fixed in version 5.15.8.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Astro | Astro | < 5.15.8 |
Related Weaknesses (CWE)
References
- https://github.com/withastro/astro/commit/6f800813516b07bbe12c666a92937525fddb58Patch
- https://github.com/withastro/astro/security/advisories/GHSA-ggxq-hp9w-j794Not Applicable
- https://github.com/withastro/astro/security/advisories/GHSA-whqg-ppgf-wp8cVendor Advisory
FAQ
What is CVE-2025-66202?
CVE-2025-66202 is a vulnerability with a CVSS score of 6.5 (MEDIUM). Astro is a web framework. Versions 5.15.7 and below have a double URL encoding bypass which allows any unauthenticated attacker to bypass path-based authentication checks in Astro middleware, granting...
How severe is CVE-2025-66202?
CVE-2025-66202 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-66202?
Check the references section above for vendor advisories and patch information. Affected products include: Astro Astro.