Cohere Terrarium contains a sandbox escape flaw that allows an attacker to execute arbitrary code with root privileges on the host system by traversing the JavaScript prototype chain. This vulnerability bypasses the intended isolation boundaries of the Terrarium environment, enabling complete takeover of the underlying host and allowing the attacker to read, modify, or delete any data and to install additional malicious software. The impact is severe, affecting confidentiality, integrity, and availability at the system level.

The affected product is Cohere Terrarium. No specific version numbers were disclosed in the advisory, so any deployment of the component that is currently running is potentially vulnerable until a patch or definitive fix is applied. Administrators should review all instances of Cohere Terrarium in their environment to gauge exposure.

The CVSS score of 9.3 categorizes this flaw as critical. The EPSS score is not available, and the vulnerability is not yet catalogued in the CISA KEV list. The attack vector is inferred to be remote, as malicious JavaScript can be injected within the sandboxed environment, and the necessary conditions include a permissive JavaScript execution context that allows prototype modifications and host resource access. Organizations running Terrarium with untrusted or permissive scripting should consider this vulnerability the highest risk exposure.