GitHub Advisoryadvisory · npm

GHSA-8mv7-9c27-98vc Astro: composable `astro/hono` pipeline bypasses `security.checkOrigin` when `middleware()` is absent or misordered

MEDIUM Published 2026-07-20 Modified 2026-08-12 Official page ↗
Aliases
CVE-2026-73423
Ecosystem
npm
Packages
astro
Severity
Moderate
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N
Weaknesses
CWE-352
Reviewed
2026-07-20

Affected packages

• npm astro: >= 7.0.0, < 7.0.6 → fixed in 7.0.6

Description

Summary In the composable `astro/hono` pipeline, the `security.checkOrigin` protection is only installed by the `middleware()` primitive. The `actions()` and `pages()` primitives each dispatch to user code independently, so a pipeline that mounts either primitive before (or without) `middleware()` will bypass the origin check for those requests. Details `security.checkOrigin` (default: `true`) is intended to reject cross-site `POST`/`PUT`/`PATCH`/`DELETE` form submissions. In the classic pipeline (`astro()` all-in-one), the check always runs because Astro injects a virtual middleware module even when the user has no `src/middleware.ts`. In the composable `astro/hono` pipeline, the user assembles primitives manually. The check is only installed inside `middleware()` — so: • Mounting `actions()` before `middleware()` allows cross-origin form-encoded action requests to execute before the gate runs. The `examples/advanced-routing` example and the Cloudflare `hono` docs shipped this order. • Omitting `middleware()` entirely (reasonable for apps with no custom middleware) silently drops `checkOrigin` protection for all on-demand endpoints and pages dispatched through `pages()`. The attack is a blind write-only CSRF: the attacker can trigger a state-mutating action or endpoint handler using the victim's cookies, but cannot read the cross-origin response body. Affected versions Astro `>= 7.0.0` when using the composable `astro/hono` pipeline with either: • `actions()` mounted before `middleware()`, or • `pages()` used without `middleware()` The default (non-composable) pipeline is not affected. Fix The origin check is now applied at each dispatch sink (`ActionHandler.handle` and `PagesHandler.handleWithErrorFallback`), gated on `manifest.checkOrigin`, using the same predicate as the middleware. The check is order-independent and a no-op when `middleware()` has already run. Fix: https://github.com/withastro/astro/pull/17250 Workaround Ensure `middleware()` is mounted before both `actions()` and `pages()` in the composable pipeline, and that it is always included even when no custom middleware logic is needed: ```ts app.use(middleware()); app.use(actions()); app.use(pages()); ```

Related

Alias · CVE (1)

  • CVE-2026-73423 Astro is a web framework for content-driven websites. vulnerability

Weakness · CWE (1)

  • CWE-352 Cross-Site Request Forgery weakness

References