Cyber Resilience

CVE-2025-66202

Medium

Published: 09 December 2025

Published
09 December 2025
Modified
10 December 2025
KEV Added
Patch
CVSS Score v3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
EPSS Score 0.0030 53.6th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-66202 is a medium-severity Use of Non-Canonical URL Paths for Authorization Decisions (CWE-647) vulnerability in Astro Astro. Its CVSS base score is 6.5 (Medium).

Operationally, ranked in the top 46.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

astro
astro
≤ 5.15.8

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References