CVE-2026-53818: OpenClaw authorization bypass in MCP loopback feature

Executive brief

OpenClaw is a tool used for managing automated tasks and gateway operations. A security flaw in its communication loopback feature could allow a standard user to bypass security policies intended only for the system owner. This could result in unauthorized users performing sensitive actions or accessing restricted tools, potentially compromising the integrity of the gateway.

Technical details

A missing authorization vulnerability (CWE-862) exists in OpenClaw's Model Context Protocol (MCP) loopback implementation. In affected versions, a non-owner caller can reach a specific loopback path that bypasses owner-only tool policies and 'before-tool-call' hooks. This allows an attacker with local access and low privileges to invoke behaviors and tools that should be restricted to the system owner. The vulnerability is reachable when the MCP loopback feature is enabled. A fix is available in version 2026.4.24.

Affected products

• openclaw openclaw < 2026.4.24

Timeline

• 2026-05-28: disclosed
• 2026-06-11: advisory: NVD publication date
• 2026-07-02: advisory: GitHub Advisory published

References

• https://api.github.com/users/zsxsoft
• https://github.com/zsxsoft
• https://api.github.com/users/zsxsoft/gists%7B/gist_id%7D
• https://api.github.com/users/zsxsoft/repos
• https://avatars.githubusercontent.com/u/2398785?v=4
• https://api.github.com/users/zsxsoft/events%7B/privacy%7D