The OpenClaw application in versions prior to 2026.4.2 fails to enforce write scopes on the POST /sessions/:sessionKey/kill endpoint when operating in identity‑bearing HTTP modes. An attacker possessing only read‑scoped credentials can send a request to this endpoint and terminate any active sub‑agent session. This lack of authorization control can lead to denial of service by disrupting legitimate sessions and may allow more aggressive attacks if repeated termination causes instability in the system. The vulnerability is a classic example of CWE-862, an improper authorization flaw.

OpenClaw OpenClaw installations running any version earlier than 2026.4.2 on Node.js are affected. Clients that expose the POST /sessions/:sessionKey/kill endpoint without enforcing proper write permissions allow this flaw.

The CVSS score of 5.3 indicates moderate severity. The EPSS score of <1% signifies a low probability of exploitation in the wild. The vulnerability is not listed in the CISA KEV catalog. The likely attack vector is remote over HTTP, particularly when an attacker can obtain a read‑scoped token. Even though the impact is limited to session termination, repeated disruptions could increase operational risk. No additional prerequisites beyond valid read scope are mentioned, so the barrier to exploitation is low for an attacker with access to the API.