CVE-2025-66202

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 v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/withastro/astro/commit/6f800813516b07bbe12c666a92937525fddb58ce	Patch
https://github.com/withastro/astro/security/advisories/GHSA-ggxq-hp9w-j794	Not Applicable
https://github.com/withastro/astro/security/advisories/GHSA-whqg-ppgf-wp8c	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:astro:astro:*:*:*:*:*:node.js:*:*

History

07 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Astro es un web framework. Las versiones 5.15.7 e inferiores tienen un bypass de doble codificación de URL que permite a cualquier atacante no autenticado omitir las comprobaciones de autenticación basadas en rutas en el middleware de Astro, otorgando acceso no autorizado a rutas protegidas. Aunque el CVE-2025-64765 original fue corregido en la v5.15.8, la corrección es insuficiente ya que solo decodifica una vez. Al usar URLs doblemente codificadas, los atacantes aún pueden omitir la autenticación y acceder a cualquier ruta protegida por las comprobaciones de nombre de ruta del middleware. Este problema está corregido en la versión 5.15.8.

Information

Published : 2025-12-09 00:15

Updated : 2026-10-07 20:10

NVD link : CVE-2025-66202

Mitre link : CVE-2025-66202

CVE.ORG link : CVE-2025-66202

JSON object : View

Products Affected

astro

astro

CWE

CWE-647

Use of Non-Canonical URL Paths for Authorization Decisions

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