CVE-2026-73423

MEDIUM CVSS 4.0: 5.1 EPSS 0.18%
Updated Aug 13, 2026
Cloudflare
Parameter Value
CVSS 5.1 (MEDIUM)
Fixed In 7.0.6
Type CWE-352 (Cross-Site Request Forgery (CSRF))
Vendor Cloudflare
Public PoC No

Astro is a web framework for content-driven websites. From 7.0.0 until 7.0.6, the composable astro/hono pipeline installs security.checkOrigin only through the middleware() primitive, while actions() and pages() can dispatch to user code independently. Mounting actions() before middleware(), as in the examples/advanced-routing example and Cloudflare Hono documentation, allows cross-origin form-encoded action requests to execute before the origin check, and using pages() without middleware() drops the check for on-demand endpoints and pages.

The flaw enables blind write-only cross-site request forgery using the victim's cookies against ActionHandler.handle and PagesHandler.handleWithErrorFallback when manifest.checkOrigin is enabled; the attacker can trigger a state-mutating action or endpoint handler but cannot read the cross-origin response. The default non-composable astro() pipeline is not affected. This issue is fixed in version 7.0.6.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
Active
User action required

Impact Assessment

Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
None
No disruption

CVSS Vector v4.0

Vulnerable Products

withastro:astro