OpenClaw's Slack allowFrom feature could bind to mutable display names, allowing a Slack account that can change its display name metadata to match a policy entry incorrectly. This vulnerability affects versions prior to 2026.5.3. The issue does not alter OpenClaw's trusted-operator model but may allow agent access intended for another Slack identity if the feature is enabled and reachable. The vulnerability is rated high severity. Mitigations include using stable Slack user IDs in allowlists until patched, narrowing channel and tool allowlists, avoiding sharing a Gateway between untrusted users, and disabling the affected feature when not needed.