Critical 9.1Published Apr 24, 2026

CVE-2026-41248Official Clerk JavaScript SDKs: Middleware-based route protection bypass

Updated under an hour ago (Oct 26, 2026, 10:00 AM ET)

Does this affect you?

It affects clerk astro and 3 other products. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for clerk astro

Exploited in the last 30 days

Clerk JavaScript is the official JavaScript repository for Clerk authentication. 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. This vulnerability is fixed in @clerk/astro 1.5.7, 2.17.10, and 3.0.15; @clerk/nextjs 5.7.6, 6.39.2, and 7.2.1; @clerk/nuxt 1.13.28 and 2.2.2; and @clerk/shared 2.22.1, 3.47.4, anc 4.8.1

CVSS: 9.1 CRITICAL (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Weakness (CWE): CWE-436, CWE-863
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Apr 27, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

clerk astro clerk:astro (from the name)	from 0.0.1, < 1.5.7; from 2.0.0-snapshot.v20241206174604, <= 2.17.9; from 3.0.0, < 3.0.15	CNA record
clerk nextjs clerk:nextjs (from the name)	from 5.0.0, < 5.7.6; from 6.0.0-snapshot.vb87a27f, < 6.39.2; from 7.0.0, < 7.2.1	CNA record
clerk nuxt clerk:nuxt (from the name)	from 1.1.0, < 1.13.28; from 2.0.0, < 2.2.2	CNA record
clerk shared clerk:shared (from the name)	from 2.20.17, < 2.22.1; from 3.0.0-canary.v20250225091530, < 3.47.4; from 4.0.0, < 4.8.1	CNA record

References

https://github.com/clerk/javascript/security/advisories/GHSA-vqx2-fgx2-5wq9x-refsource-confirm

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.