@clerk/backend Performs Insufficient Verification of Data Authenticity
Priority LOW 38CWE-345Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-345.
Summary
Clerk helps developers build user management. Applications that use the verifyWebhook() helper to verify incoming Clerk webhooks are susceptible to accepting improperly signed webhook events. The issue was resolved in @clerk/backend 2.4.0.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00172 6th percentileScored 2026-11-07
Fix Fixed javascript (clerk): 2.4.0@clerk/backend (npm): 2.4.0+8 more products
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| clerk | javascript | before 2.4.0 | 2.4.0 | Patch available | CNA |
| — | @clerk/backend (npm) | 2.0.0 to before 2.4.0 | 2.4.0 | Patch available | GHSA-9mp4-77wg-rwx9 |
| — | @clerk/astro (npm) | 2.9.0 to before 2.10.2 | 2.10.2 | Patch available | GHSA-9mp4-77wg-rwx9 |
| — | @clerk/express (npm) | 1.6.0 to before 1.7.4 | 1.7.4 | Patch available | GHSA-9mp4-77wg-rwx9 |
| — | @clerk/fastify (npm) | 2.3.0 to before 2.4.4 | 2.4.4 | Patch available | GHSA-9mp4-77wg-rwx9 |
| — | @clerk/nextjs (npm) | 6.2.10 to before 6.23.3 | 6.23.3 | Patch available | GHSA-9mp4-77wg-rwx9 |
| — | @clerk/nuxt (npm) | 1.7.0 to before 1.7.5 | 1.7.5 | Patch available | GHSA-9mp4-77wg-rwx9 |
| — | @clerk/react-router (npm) | 1.5.0 to before 1.6.4 | 1.6.4 | Patch available | GHSA-9mp4-77wg-rwx9 |
| — | @clerk/remix (npm) | 4.8.0 to before 4.8.5 | 4.8.5 | Patch available | GHSA-9mp4-77wg-rwx9 |
| — | @clerk/tanstack-react-start (npm) | 0.16.0 to before 0.18.3 | 0.18.3 | Patch available | GHSA-9mp4-77wg-rwx9 |
- javascript Vendorclerk Affected before 2.4.0 Fixed in 2.4.0 Patch available CNA
- @clerk/backend (npm) Vendor— Affected 2.0.0 to before 2.4.0 Fixed in 2.4.0 Patch available GHSA-9mp4-77wg-rwx9
- @clerk/astro (npm) Vendor— Affected 2.9.0 to before 2.10.2 Fixed in 2.10.2 Patch available GHSA-9mp4-77wg-rwx9
- @clerk/express (npm) Vendor— Affected 1.6.0 to before 1.7.4 Fixed in 1.7.4 Patch available GHSA-9mp4-77wg-rwx9
- @clerk/fastify (npm) Vendor— Affected 2.3.0 to before 2.4.4 Fixed in 2.4.4 Patch available GHSA-9mp4-77wg-rwx9
- @clerk/nextjs (npm) Vendor— Affected 6.2.10 to before 6.23.3 Fixed in 6.23.3 Patch available GHSA-9mp4-77wg-rwx9
- @clerk/nuxt (npm) Vendor— Affected 1.7.0 to before 1.7.5 Fixed in 1.7.5 Patch available GHSA-9mp4-77wg-rwx9
- @clerk/react-router (npm) Vendor— Affected 1.5.0 to before 1.6.4 Fixed in 1.6.4 Patch available GHSA-9mp4-77wg-rwx9
- @clerk/remix (npm) Vendor— Affected 4.8.0 to before 4.8.5 Fixed in 4.8.5 Patch available GHSA-9mp4-77wg-rwx9
- @clerk/tanstack-react-start (npm) Vendor— Affected 0.16.0 to before 0.18.3 Fixed in 0.18.3 Patch available GHSA-9mp4-77wg-rwx9
Remediation
- Fix · CNA javascript (clerk) Fixed in 2.4.0
- Fix · GHSA-9mp4-77wg-rwx9 @clerk/backend (npm) Fixed in 2.4.0 Advisory →
- Fix · GHSA-9mp4-77wg-rwx9 @clerk/astro (npm) Fixed in 2.10.2 Advisory →
- Fix · GHSA-9mp4-77wg-rwx9 @clerk/express (npm) Fixed in 1.7.4 Advisory →
- Fix · GHSA-9mp4-77wg-rwx9 @clerk/fastify (npm) Fixed in 2.4.4 Advisory →
- Fix · GHSA-9mp4-77wg-rwx9 @clerk/nextjs (npm) Fixed in 6.23.3 Advisory →
- Fix · GHSA-9mp4-77wg-rwx9 @clerk/nuxt (npm) Fixed in 1.7.5 Advisory →
- Fix · GHSA-9mp4-77wg-rwx9 @clerk/react-router (npm) Fixed in 1.6.4 Advisory →
- Fix · GHSA-9mp4-77wg-rwx9 @clerk/remix (npm) Fixed in 4.8.5 Advisory →
- Fix · GHSA-9mp4-77wg-rwx9 @clerk/tanstack-react-start (npm) Fixed in 0.18.3 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2025-53548
- 2026-10-03 Alias added: GHSA-9mp4-77wg-rwx9
References
More clerk vulnerabilities
- TI-2026-30651 Clerk: Authorization bypass when combining organization, billing, or reverification checks CVSS 4.0HIGH 7.6
- TI-2024-14799 @clerk/nextjs auth() and getAuth() methods vulnerable to insecure direct object reference (IDOR) CVSS 3.1CRITICAL 9.8
- TI-2026-29857 Official Clerk JavaScript SDKs: Middleware-based route protection bypass CVSS 3.1CRITICAL 9.1
- TI-2026-26399 Clerk JavaScript: SSRF in the opt-in clerkFrontendApiProxy feature may leak secret keys to unintended host CVSS 3.1HIGH 7.4
Sources
- CVE-2025-53548 · CVE Program
- CVE-2025-53548 · NVD
- FIRST EPSS
- GHSA-9mp4-77wg-rwx9 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences