Authenticated arbitrary file write via traversed document identifier

Path traversal in Stamus Networks Scirius 3.8.0 and earlier allows remote authenticated users to write JSON files as root. The PCAP filestore upload handler passes the uploaded document's attacker-controlled _id value to os.path.join without rejecting traversal and then writes the resulting .json path. A default User role and access to the authenticated endpoint are sufficient; under the official container configuration, the write can alter files accessible to the root process.