What’s Vulnerable › Vulnerabilities
CVE-2026-41248: Official Clerk JavaScript SDKs: Middleware-based route protection bypass
- Severity: critical (CVSS 9.1 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.3% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-04-24 · updated 2026-10-26
- Weakness: CWE-436
Description
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
Affected products
- clerk astro: from 0.0.1, < 1.5.7; from 2.0.0-snapshot.v20241206174604, <= 2.17.9; from 3.0.0, < 3.0.15
- clerk nextjs: from 5.0.0, < 5.7.6; from 6.0.0-snapshot.vb87a27f, < 6.39.2; from 7.0.0, < 7.2.1
- clerk nuxt: from 1.1.0, < 1.13.28; from 2.0.0, < 2.2.2
- clerk shared: from 2.20.17, < 2.22.1; from 3.0.0-canary.v20250225091530, < 3.47.4; from 4.0.0, < 4.8.1
References
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