Vulnerability library
Security checkApril 27, 2026

Official Clerk JavaScript SDKs: Middleware-based route protection bypass - @clerk/astro

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High severitynpm@clerk/astro

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Description

createRouteMatcher in @clerk/nextjs, @clerk/nuxt, and @clerk/astro can be bypassed by certain crafted requests, allowing them to skip middleware gating and reach downstream handlers.

Sessions are not compromised and no existing user can be impersonated - the bypass only affects the middleware-level gating decision.

Recommendation

Update the @clerk/astro package to the latest compatible version. Followings are version details:

  • Affected version(s): **>= 3.0.0, < 3.0.15 >= 2.0.0-snapshot.v20241206174604, <= 2.17.9 >= 0.0.1, < 1.5.7**
  • Patched version(s): **3.0.15 2.17.10 1.5.7**

References

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Related Issues

See something that needs correcting? Let us knowUpdated April 27, 2026