Directus is a real-time API and App dashboard for managing SQL database content. Prior to 11.17.0, the PATCH /files/{id} endpoint accepts a user-controlled filename_disk parameter. By setting this value to match the storage path of another user's file, an attacker can overwrite that file's content while manipulating metadata fields such as uploaded_by to obscure the tampering. This vulnerability is fixed in 11.17.0.
Use CWE-284, Monospace vendor hub and Directus product page to widen CVE-2026-39942 into its surrounding weakness, vendor, and product context.
Compare it with CVE-2026-35408, CVE-2026-35442 and CVE-2026-35409 for nearby disclosures in the same product family.