CVE-2026-73423: Astro: composable `astro/hono` pipeline bypasses `security.checkOrigin` when `middleware()` is absent or misordered
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.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Astro (astro/hono composable pipeline)to a version that resolves this vulnerability.Fixed in 7.0.6
Event History
Frequently Asked Questions
What is the severity of CVE-2026-73423?
The severity of CVE-2026-73423 is rated at 52, indicating a moderate risk level.
How do I fix CVE-2026-73423?
To fix CVE-2026-73423, ensure that security.checkOrigin is properly set up by correctly ordering the middleware() in your astro/hono pipeline.
Which versions of Astro are affected by CVE-2026-73423?
CVE-2026-73423 affects Astro versions from 7.0.0 to 7.0.6.
What type of vulnerability is CVE-2026-73423 classified as?
CVE-2026-73423 is classified as a Cross-Site Request Forgery (CSRF) vulnerability.
What are the potential impacts of CVE-2026-73423?
The potential impacts of CVE-2026-73423 include unauthorized actions being performed on behalf of an authenticated user due to the lack of proper origin checks.