OpenClaw versions prior to 2026.2.21 incorrectly allow prototype-reserved keys (__proto__, constructor, prototype) to be supplied in the runtime /debug set override object. This creates a prototype pollution flaw that can be used to alter built‑in object prototypes. Because the /debug set is protected by a command gate, an attacker who is authorized to use this API can inject these keys and bypass the gate, potentially executing arbitrary code. The flaw is classified as CWE‑1321: Prototype Pollution.

All installations of OpenClaw before version 2026.2.21 are vulnerable. The affected product is OpenClaw (OpenClaw:OpenClaw) running on Node.js environments. The CVE references a source commit that applies the patch for 2026.2.21, indicating that upgrades to this version or later contain the fix.

The CVSS base score is 2.3, reflecting a low severity. The EPSS score is not available and the vulnerability is not listed in CISA's KEV catalog. Exploitation requires an authenticated caller that has permission to invoke the /debug set API, which is typically a privileged user or developer environment. If this access is available, an attacker can modify prototypes and bypass authentication controls, suggesting a higher impact in that context. Overall, the risk is low for general users but could become significant if the /debug API is exposed to untrusted parties.