CVE-2026-41248 in the critical feed json
Official Clerk JavaScript SDKs: Middleware-based route protection bypass
published 6mo ago modified 14d ago also GHSA-vqx2-fgx2-5wq9 , EUVD-2026-25632
- cvss
- 9.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 25%
- public exploits
- 0
- none known
Summary
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
Patch / fix
- npm @clerk/nextjs 5.7.6, 6.39.2, 7.2.1
- npm @clerk/nuxt 1.13.28, 2.2.2
- npm @clerk/astro 1.5.7, 2.17.10, 3.0.15
- npm @clerk/shared 2.22.1, 3.47.4, 4.8.1
Is CVE-2026-41248 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 6mo ago
Exploit prediction
0.32% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
| GitHub | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | @clerk/nextjs | >=5.0.0, <5.7.6 >=6.0.0-snapshot.vb87a27f, <6.39.2 >=7.0.0, <7.2.1 |
5.7.6 6.39.2 7.2.1 |
| npm | @clerk/nuxt | >=1.1.0, <1.13.28 >=2.0.0, <2.2.2 |
1.13.28 2.2.2 |
| npm | @clerk/astro | >=0.0.1, <1.5.7 >=2.0.0-snapshot.v20241206174604, <2.17.10 >=3.0.0, <3.0.15 |
1.5.7 2.17.10 3.0.15 |
| npm | @clerk/shared | >=2.20.17, <2.22.1 >=3.0.0-canary.v20250225091530, <3.47.4 >=4.0.0, <4.8.1 |
2.22.1 3.47.4 4.8.1 |
Affected products
- clerk astro
- clerk nextjs
- clerk nuxt
- clerk shared
Classification
- Weakness
- Technology feeds
References
Sources
- CVE List CVE-2026-41248
- GitHub Advisory GHSA-vqx2-fgx2-5wq9
- NVD CVE-2026-41248
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.