---
cve: "CVE-2025-66202"
severity: "MEDIUM"
cvss: 6.5
epss: "32%"
vendor: "withastro"
kev: false
exploited: false
published: "2025-12-09 00:15:48"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-06T15:23:52+02:00"
---

# CVE-2025-66202

> 6.5 MEDIUM · 🧪 PoC

## Beschreibung

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-Vektor

```
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Gering | warn |
| I Integrität | Gering | warn |
| A Verfügbarkeit | Keine | good |

## Patch verfügbar (OSV)

- 60af4d0a1a56d8db56e3d737f4f9ea680203490e (Commit)
- 6f800813516b07bbe12c666a92937525fddb58ce (Commit)

## Referenzen

- <https://github.com/withastro/astro/security/advisories/GHSA-whqg-ppgf-wp8c>
- <https://github.com/withastro/astro/security/advisories/GHSA-ggxq-hp9w-j794>
- <https://github.com/withastro/astro/commit/6f800813516b07bbe12c666a92937525fddb58ce>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2025-66202) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_