CVE-2026-34076
Description
Clerk JavaScript is the official JavaScript repository for Clerk authentication. In @clerk/hono from versions 0.1.0 to before 0.1.5, @clerk/express from versions 2.0.0 to before 2.0.7, @clerk/backend from versions 3.0.0 to before 3.2.3, and @clerk/fastify from versions 3.1.0 to before 3.1.5, the clerkFrontendApiProxy function in @clerk/backend is vulnerable to Server-Side Request Forgery (SSRF). An unauthenticated attacker can craft a request path that causes the proxy to send the application's Clerk-Secret-Key to an attacker-controlled server. This issue has been patched in @clerk/hono version 0.1.5, @clerk/express version 2.0.7, @clerk/backend version 3.2.3, and @clerk/fastify version 3.1.5.
How to fix
- @clerk/backend3.2.3 or later
- @clerk/express2.0.7 or later
- @clerk/hono0.1.5 or later
- @clerk/fastify3.1.5 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| @clerk/backendnpm | 3.0.0 ≤ v < 3.2.3 | 3.2.3 |
| @clerk/expressnpm | 2.0.0 ≤ v < 2.0.7 | 2.0.7 |
| @clerk/hononpm | 0.1.0 ≤ v < 0.1.5 | 0.1.5 |
| @clerk/fastifynpm | 3.1.0 ≤ v < 3.1.5 | 3.1.5 |
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Attack Surface Management
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