CVE-2026-42349
Last modified
CVE-2026-42349 is a high-severity vulnerability rated 7.6/10 on the CVSS scale. Clerk JavaScript is the official JavaScript repository for Clerk authentication. has(), auth.protect(), and related authorization predicates in @clerk/shared, @clerk/nextjs, @clerk/backend, and other framework SDKs can return true for certain combined authorization checks when the result should be false, allowing a gated action to proceed for a user who does not satisfy the full set of requested conditions. EPSS estimates a 0.25% chance of exploitation in the next 30 days.
Description
Clerk JavaScript is the official JavaScript repository for Clerk authentication. has(), auth.protect(), and related authorization predicates in @clerk/shared, @clerk/nextjs, @clerk/backend, and other framework SDKs can return true for certain combined authorization checks when the result should be false, allowing a gated action to proceed for a user who does not satisfy the full set of requested conditions. This call shape can be bypassed if certain conditions are met: a has() or auth.protect() call that combines a reverification check with any of role, permission, feature, or plan, or that combines a billing check (feature or plan) with a role or permission check. This vulnerability is fixed in @clerk/clerk-js 5.125.10 and 6.7.5.
Metrics
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Clerk | Clerk\/Astro | >= 2.0.0, < 2.17.11 |
| Clerk | Clerk\/Astro | >= 3.0.0, < 3.0.18 |
| Clerk | Clerk\/Backend | >= 2.0.0, < 2.33.3 |
| Clerk | Clerk\/Backend | >= 3.0.0, < 3.2.14 |
| Clerk | Clerk\/Chrome-Extension | >= 1.3.5, < 2.9.15 |
| Clerk | Clerk\/Chrome-Extension | >= 3.0.0, < 3.1.15 |
| Clerk | Clerk\/Clerk-Expo | >= 2.2.11, < 2.19.36 |
| Clerk | Clerk\/Clerk-Js | >= 5.22.0, < 5.125.10 |
| Clerk | Clerk\/Clerk-Js | >= 6.0.0, < 6.7.5 |
| Clerk | Clerk\/Clerk-React | >= 5.9.0, < 5.61.6 |
| Clerk | Clerk\/Expo | >= 3.0.0, < 3.2.2 |
| Clerk | Clerk\/Express | >= 0.1.0, < 1.7.79 |
| Clerk | Clerk\/Express | >= 2.0.0, < 2.1.6 |
| Clerk | Clerk\/Fastify | >= 1.0.42, < 2.6.31 |
| Clerk | Clerk\/Fastify | >= 3.0.0, < 3.1.16 |
| Clerk | Clerk\/Hono | >= 0.0.2, < 0.1.16 |
| Clerk | Clerk\/Nextjs | >= 6.0.0, <= 6.39.3 |
| Clerk | Clerk\/Nextjs | >= 7.0.0, < 7.2.4 |
| Clerk | Clerk\/Nuxt | >= 1.0.0, < 1.13.29 |
| Clerk | Clerk\/Nuxt | >= 2.0.0, < 2.2.5 |
| Clerk | Clerk\/React | >= 6.0.0, < 6.4.3 |
| Clerk | Clerk\/React-Router | >= 0.0.1, < 2.4.13 |
| Clerk | Clerk\/React-Router | >= 3.0.0, < 3.1.4 |
| Clerk | Clerk\/Shared | >= 3.0.0, < 3.47.5 |
| Clerk | Clerk\/Shared | >= 4.0.0, < 4.8.3 |
| Clerk | Clerk\/Tanstack-React-Start | >= 0.0.1, < 0.29.11 |
| Clerk | Clerk\/Tanstack-React-Start | >= 1.0.0, < 1.1.4 |
| Clerk | Clerk\/Vue | >= 1.0.0, < 1.17.21 |
| Clerk | Clerk\/Vue | >= 2.0.0, < 2.0.16 |
References
- https://github.com/clerk/javascript/security/advisories/GHSA-w24r-5266-9c3cMitigation, Vendor Advisory
- https://github.com/clerk/javascript/security/advisories/GHSA-w24r-5266-9c3cMitigation, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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