Flowise Broken Access Control in /api/v1/files

Flowise versions 3.1.2 and earlier contain a broken access control vulnerability (CVE-2026-69252) in the /api/v1/files endpoint. The application fails to verify workspace-level permissions, only checking for a general feature flag. Consequently, any authenticated API key - regardless of assigned role - can list and delete files stored in any workspace belonging to the same organization. An attacker with a restricted API key can exfiltrate metadata about files in other workspaces or permanently delete sensitive assets, effectively bypassing the organization's intended workspace isolation boundaries.

Attack Chain

1. Attacker creates or obtains an API key with minimal permissions (e.g., tools:view) via legitimate account access.
2. Attacker inspects the /api/v1/files endpoint to identify accessible file paths.
3. Attacker sends a GET request to /api/v1/files using their low-privileged Authorization: Bearer token.
4. The application logic fails to check activeWorkspaceId, returning a list of all files across the entire organization.
5. Attacker parses the JSON response to extract paths belonging to target workspaces.
6. Attacker sends a DELETE request to /api/v1/files with the path parameter set to a file located in a foreign workspace.
7. The application performs the deletion using the organization ID context, successfully removing the unauthorized file.

Impact

Successful exploitation results in the unauthorized exposure of file metadata and destructive tampering of workspace data. An attacker can systematically delete files across an entire organization, leading to significant data loss and disruption of business processes for affected users and workspaces.

Recommendation

• Update Flowise to a version where CVE-2026-69252 is patched.
• Implement request monitoring for the /api/v1/files endpoint to identify users accessing paths outside their assigned workspace directory.
• Deploy the Sigma rule below to detect unauthorized file deletion attempts by low-privileged API keys.