CVE-2026-28459: OpenClaw < 2026.2.12 - Arbitrary File Write via Untrusted sessionFile Path

OpenClaw versions prior to 2026.2.12 fail to validate the sessionFile path parameter, allowing authenticated gateway clients to write transcript data to arbitrary locations on the host filesystem. Attackers can supply a sessionFile path outside the sessions directory to create files and append data repeatedly, potentially causing configuration corruption or denial of service.