Disclosure summary
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.
Source-reported weakness categories
CWE-647
Source-specific records & product guidance
Sources retain their own attribution and scoring. Follow the original record to confirm affected versions, fixed releases, and configuration conditions.
NIST National Vulnerability Database · NVD-CVE-2025-66202
Open original source · Updated Oct 07, 2026
Only CPE matches marked vulnerable=true are indexed. AND/OR platform conditions must be checked in the original NVD record.
| Vendor | Product / association | Version / bounds |
|---|---|---|
| astro | astro | * {"versionEndExcluding":"5.15.8"} |
Original records & references
- NIST NVD record
- CVE Program record
- github.com — Patch
- github.com — Not Applicable
- github.com — Vendor Advisory
PUBLISHED 2025-12-08T19:15:48-05:00
MODIFIED 2026-10-07T16:10:01-04:00
INGESTED 2026-10-08T12:35:36-04:00