CVE-2026-34076

Clerk JavaScript: SSRF in the opt-in clerkFrontendApiProxy feature may leak secret keys to unintended host

Published Apr 1, 2026 CVSS 3.1 · 7.4 High EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-gjxx-92w9-8v8f Clerk: SSRF in the opt-in clerkFrontendApiProxy feature may leak secret keys to unintended host
History
Type Values Removed Values Added
First Time appeared Clerk
Clerk javascript
Vendors & Products Clerk
Clerk javascript
Type Values Removed Values Added
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.
Title Clerk JavaScript: SSRF in the opt-in clerkFrontendApiProxy feature may leak secret keys to unintended host
Weaknesses CWE-918
References
Metrics cvssV3_1

{'score': 7.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Apr 1, 2026, 6:00 PM
Reserved
Mar 25, 2026, 4:21 PM
Status
Deferred
Published
Apr 1, 2026, 6:16 PM
Modified
Oct 26, 2026, 10:10 PM