CVE-2026-34076
HIGHClerk JavaScript: SSRF in the opt-in clerkFrontendApiProxy feature may leak secret keys to unintended host
Title source: cnaDescription
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.
Scores
CVSS v3
7.4
EPSS
0.0002
EPSS Percentile
4.4%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
total
Details
CWE
CWE-918
Status
published
Products (8)
clerk/backend
3.0.0 - 3.2.3npm
clerk/express
2.0.0 - 2.0.7npm
clerk/fastify
3.1.0 - 3.1.5npm
clerk/hono
0.1.0 - 0.1.5npm
clerk/javascript
@clerk/backend >= 3.0.0, < 3.2.3
clerk/javascript
@clerk/express >= 2.0.0, < 2.0.7
clerk/javascript
@clerk/fastify >= 3.1.0, < 3.1.5
clerk/javascript
@clerk/hono >= 0.1.0, < 0.1.5
Published
Apr 01, 2026
Tracked Since
Apr 01, 2026