Stirling‑PDF 3.0.0 through 3.2.0 contains an authorization bypass flaw that allows an authenticated user to point a processing folder at a server‑side storage directory belonging to another user. By creating a folder via POST /api/v1/processing‑folders targeting storage/<victimUserId>, the attacker can list and enumerate files, and run processing pipelines that read, modify, or delete the victim’s stored files. This demonstrates a classic privilege escalation under CWE‑639, enabling compromise of confidentiality, integrity, and availability for affected users.

The vulnerability affects the Stirling‑Tools Stirling‑PDF product across all releases from 3.0.0 through 3.2.0. No specific sub‑components or additional product families are listed beyond Stirling‑PDF itself.

The CVSS score of 7.1 indicates a medium‑high severity. The EPSS score is not available, and the vulnerability is not listed in CISA’s KEV catalog. The likely attack vector is via the documented HTTP API endpoint, requiring only authenticated access but no elevated privileges. An attacker who can authenticate with any user account can exploit the flaw to gain access to files of any other user, presenting a significant risk to confidentiality and integrity for all deployed instances.