Executive brief
Payload is a popular Node.js headless CMS used for managing and serving content through APIs. The vulnerability allows authenticated users with upload permissions to access internal network resources by exploiting insufficient validation of HTTP redirects during external file uploads, potentially exposing sensitive internal services and data.
Technical details
Payload versions prior to v3.75.0 contain a Server-Side Request Forgery (SSRF) vulnerability (CWE-918) in the external file upload functionality. The vulnerability stems from insufficient validation of HTTP redirects when processing external URLs for file uploads. An authenticated user with write permissions on an upload-enabled collection can craft a malicious URL that exploits redirect handling to access internal network resources. The attack requires authentication and collection-level create access, but no user interaction. Successful exploitation allows retrieval of response content from internal services, potentially exposing sensitive data. The vulnerability has been patched in v3.75.0; users can also mitigate by disabling external file uploads or restricting collection access to trusted users.
Affected products
- Payload CMS Payload < 3.75.0
Timeline
- 2026-02-24: disclosed
- 2026-02-24: patched: v3.75.0 released