CVE-2026-28482: OpenClaw's unsanitized session ID enables path traversal in transcript file operations

Description

OpenClaw versions <= 2026.2.9 construct transcript file paths using an unsanitized sessionId and also accept sessionFile paths without enforcing that they stay within the agent sessions directory.

A crafted sessionId and/or sessionFile (example: ../../etc/passwd) can cause path traversal when the gateway performs transcript file read/write operations.

Preconditions: an attacker must be able to authenticate to the gateway (gateway token/password). By default the gateway binds to loopback (local-only); configurations that expose the gateway widen the attack surface.

Affected Packages / Versions

• Package: openclaw (npm)
• Affected: <= 2026.2.9
• Fixed: >= 2026.2.12

Fix

Fixed by validating session IDs (rejecting path separators / traversal sequences) and enforcing sessions-directory containment for session transcript file operations.

Fix Commit(s)

• 4199f9889f0c307b77096a229b9e085b8d856c26

Additional Hardening

• cab0abf52ac91e12ea7a0cf04fff315cf0c94d64

Mitigation

Upgrade to openclaw >= 2026.2.12.

Thanks @akhmittra for reporting.