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Clerk\/astroApplication · Clerk

CVE-2026-42349

HIGH · 8.1 CVSS v3.1 Published 2026-05-11
Fix available
A fix is available. Upgrade to 1.7.79 / 2.1.6 or later.
See remediation →
87/100
Remediation priority · High
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Authorization bypass in Clerk JavaScript SDK where has(), auth.protect(), and related predicates incorrectly return true for combined authorization checks. Specifically, when reverification is combined with role/permission/feature/plan checks, or when billing checks (feature/plan) are combined with role/permission checks, the authorization succeeds incorrectly, allowing users to access gated actions they shouldn't satisfy.

MitigationUpgrade @clerk/clerk-js to version 5.125.10 or 6.7.5 (or later). Audit existing code using combined authorization checks (has() or auth.protect() with reverification + roles/permissions/features/plans, or billing + roles/permissions) to verify correct behavior after upgrade.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Clerk\/astroApplication
Affected:>= 2.0.0, < 2.17.11>= 3.0.0, < 3.0.18
Clerk\/backendApplication
Affected:>= 2.0.0, < 2.33.3>= 3.0.0, < 3.2.14
Clerk\/chrome ExtensionWeb browser
Affected:>= 1.3.5, < 2.9.15>= 3.0.0, < 3.1.15
Clerk\/clerk ExpoApplication
Affected:>= 2.2.11, < 2.19.36
Clerk\/clerk JsApplication
Affected:>= 5.22.0, < 5.125.10>= 6.0.0, < 6.7.5
Clerk\/clerk ReactFramework / library
Affected:>= 5.9.0, < 5.61.6
Clerk\/expoApplication
Affected:>= 3.0.0, < 3.2.2
Clerk\/expressApplication
Affected:>= 0.1.0, < 1.7.79>= 2.0.0, < 2.1.6

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed Clerk package versions
    Run 'npm list @clerk/clerk-js @clerk/clerk-react @clerk/backend @clerk/astro @clerk/express @clerk/expo @clerk/clerk-expo' or check package.json to see the exact versions of installed Clerk packages
    Affected if Any installed version falls within the affected ranges: @clerk/clerk-js < 5.125.10 or < 6.7.5; @clerk/clerk-react < 5.61.6; @clerk/backend < 2.33.3 or < 3.2.14; @clerk/astro < 2.17.11 or < 3.0.18; @clerk/express < 1.7.79 or < 2.1.6; @clerk/expo < 3.2.2; @clerk/clerk-expo < 2.19.36
  2. Find has() authorization checks
    Search codebase for usages of 'has(' function from Clerk SDKs, particularly in authorization-related files. Look for patterns like 'has({...})' or 'has([...])' with multiple conditions
    Affected if The has() function is being used with combined conditions - specifically reverification combined with role/permission/feature/plan, or billing features combined with role/permission checks
  3. Find auth.protect() authorization predicates
    Search codebase for 'auth.protect(' or 'auth().protect(' calls. Inspect the arguments passed to see if multiple authorization criteria are combined in a single call
    Affected if auth.protect() is called with combined predicates that mix reverification with role/permission/feature/plan, or mix billing (feature/plan) with role/permission checks
  4. Review authorization logic for combined checks
    Examine files containing authorization middleware, permission guards, or role-based access control. Look for logic where multiple authorization conditions are ANDed together or passed as an array to has() or protect()
    Affected if Authorization code contains combined checks that could allow unauthorized users to pass - specifically reverification + role/permission/feature/plan combinations, or billing + role/permission combinations

A user is affected if they have a Clerk SDK version in the affected ranges AND their application uses has() or auth.protect() with combined authorization checks involving reverification plus role/permission/feature/plan, or billing features plus role/permission.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.7.79 / 2.1.6 / 2.9.15 or later
Fixed in 1.7.792.1.62.9.15
Interim mitigation

Upgrade @clerk/clerk-js to version 5.125.10 or 6.7.5 (or later). Audit existing code using combined authorization checks (has() or auth.protect() with reverification + roles/permissions/features/plans, or billing + roles/permissions) to verify correct behavior after upgrade.

Recommended fix High confidence

Upgrade all @clerk/* packages to versions >= 2.17.11 (v2) / 3.0.18 (v3) for astro/backend, >= 5.125.10 / 6.7.5 for clerk-js, >= 5.61.6 for clerk-react, >= 2.19.36 for clerk-expo, >= 1.7.79 / 2.1.6 for express, >= 3.2.2 for expo

  1. Identify all @clerk/* packages in your project by reviewing package.json dependencies
  2. Run 'npm list @clerk/*' or 'pnpm list @clerk/*' to see current installed versions
  3. For each affected package, upgrade to the minimum fixed version or the latest stable release
  4. Upgrade @clerk/clerk-js to version 5.125.10 (for v5) or 6.7.5 (for v6)
  5. Upgrade @clerk/clerk-react to version 5.61.6 or later
  6. Upgrade @clerk/backend to version 2.33.3 (for v2) or 3.2.14 (for v3)
  7. Upgrade @clerk/nextjs to the corresponding fixed version (2.17.11 for v2, 3.0.18 for v3)
  8. Upgrade @clerk/astro to version 2.17.11 (for v2) or 3.0.18 (for v3)
Caveat Review Clerk migration guides as some authorization behavior changes may affect existing logic; test extensively before deploying to production

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Clerk\/astro Scoped from the published advisory
  • Consultation4.0 h
  • Implementation2.0 h
  • Testing6.0 h
  • Review / QA3.0 h
15.0 hours of engineering $2,600
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

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