CVE-2026-81730: Dolibarr 9.0.0 through 23.0.4 Path Traversal via EmailCollector Attachment Filename

Dolibarr 9.0.0 through 23.0.4 saves inbound email attachments under the name supplied in the message's MIME headers without reducing it to a safe basename. The global saveAttachment() in htdocs/emailcollector/lib/emailcollector.lib.php builds $filepath = $path . $filename . '.' . $ext and hands it to fileputcontents(), and the private saveAttachment() in htdocs/emailcollector/class/emailcollector.class.php writes to $destdir.'/'.$filename; the name reaches both from the attachment's own getName() or getFilename() value by way of the record-join, create-ticket and create-project operations. A traversal sequence in the filename therefore survives intact, so any sender who can email a mailbox that an EmailCollector monitors, which is the module's ordinary use for a support or ticket inbox, can place attacker-controlled content outside the per-object attachment directory without holding a Dolibarr account. Under the hardened layout Dolibarr's SECURITY.md requires, with htdocs read-only, the write is confined to the documents tree and corrupts or forges other objects' documents; where htdocs is writable the same primitive reaches a web-executable path. Version 24.0.0 applies dolsanitizePathName() and dolsanitizeFileName() before the write.