GHSA-4m3v-q747-pc6h: OpenClaw: Mattermost slash token revocation could lag until monitor refresh

OpenClaw validates Mattermost slash commands with a token. The monitor that holds the valid tokens only refreshed periodically. After an operator rotated or revoked a token, the monitor still accepted the old one until the next refresh. The advisory does not give the length of that window or name the code involved.

The attacker must hold the old token, for example a leaked or former one, and must reach the slash command endpoint over the network. The CVSS 4.0 vector shows no privileges, no user interaction, an attack requirement, and low integrity impact. They could invoke slash command behaviour for a short time after the operator thought access was cut. Anything the slash commands can do in your setup is in scope, and that depends on your configuration and tool allowlists.

The flaw is a revocation gap, not a way to obtain a token. An attacker without a previously valid token gains nothing from it.

Affected: npm openclaw up to and including 2026.4.23. Only deployments with the Mattermost slash feature enabled and reachable are exposed.

npm ls -g openclaw

Drop -g for a project install. Check your Gateway configuration for Mattermost slash commands.

Update to openclaw 2026.4.24, the first stable patched version.

npm install -g [email protected]

Until you can update, restart or refresh the Mattermost monitor after every token rotation. The advisory also suggests narrow channel and tool allowlists, not sharing one Gateway between mutually untrusted users, and disabling the feature if you do not need it.

The advisory lists no log line. After a slash token rotation on an affected version, check Mattermost slash command requests that reached OpenClaw before the monitor refreshed or restarted. Look for commands authenticated with the old token or sent from unfamiliar users or IPs. Treat any token you rotated because of a leak as usable until you restart the monitor.

Summary

Mattermost slash token revocation could lag until monitor refresh. In affected versions, a caller with an old Mattermost slash token during the refresh window could continue accepting the old token until the monitor refreshed.

This advisory is scoped to the named feature and configuration. It does not change OpenClaw's trusted-operator model: authenticated Gateway operators, installed plugins, and intentional local execution surfaces remain trusted unless a separate policy, approval, allowlist, sandbox, or auth boundary is crossed.

Impact

When the affected feature is enabled and reachable, this could invoke slash command behavior briefly after token revocation. Practical impact depends on the operator's configuration and whether lower-trust input can reach that path.

Patched Versions

The first stable patched version is 2026.4.24.

Mitigations

restart or refresh the Mattermost monitor after token rotation until patched. As general hardening, keep channel and tool allowlists narrow, avoid sharing one Gateway between mutually untrusted users, and disable the affected feature when it is not needed.