CVE-2026-31975 is an OS Command Injection vulnerability classified under CWE-78 affecting siteboon's Cloud CLI (claudecodeui) prior to version 1.25.0. The vulnerability exists because the application accepts WebSocket messages containing parameters projectPath and initialCommand, which are directly embedded into bash command strings in server/index.js without any input sanitization or validation. This unsafe interpolation allows an attacker to inject arbitrary shell commands, leading to remote code execution on the host system. A secondary injection vector is present via the sessionId parameter, which is also unsanitized before use in shell commands. The vulnerability is exploitable remotely over the network without authentication or user interaction, as the WebSocket interface is exposed. The CVSS 4.0 vector indicates network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:L), no user interaction (UI:N), and high impact on confidentiality, integrity, and availability (all high). The scope is unchanged, meaning the vulnerability affects only the vulnerable component. This flaw can allow attackers to fully compromise affected systems, execute arbitrary commands, and potentially pivot within networks. The vulnerability was publicly disclosed on March 11, 2026, and fixed in version 1.25.0 of claudecodeui. No public exploits have been reported yet, but the nature of the flaw makes it a critical risk for any deployment of affected versions.

The impact of CVE-2026-31975 is severe for organizations using siteboon's Cloud CLI prior to version 1.25.0. Successful exploitation allows remote attackers to execute arbitrary OS commands with the privileges of the application, potentially leading to full system compromise. This can result in data theft, unauthorized access, disruption of services, and lateral movement within corporate networks. Since the vulnerability requires no authentication or user interaction, attackers can exploit it remotely and stealthily. Organizations relying on affected tools for development or operational workflows may face significant operational risks, including loss of intellectual property, exposure of sensitive data, and damage to reputation. The vulnerability could also be leveraged as an initial entry point for broader attacks, especially in environments where these tools are integrated with critical infrastructure or cloud services.

To mitigate CVE-2026-31975, organizations should immediately upgrade claudecodeui to version 1.25.0 or later, where the vulnerability is patched. Until upgrading is possible, restrict network access to the WebSocket interface to trusted users and networks only, using firewall rules or VPNs. Implement strict input validation and sanitization on all parameters received via WebSocket messages, especially projectPath, initialCommand, and sessionId, to prevent injection of shell metacharacters. Employ application-layer firewalls or intrusion detection systems capable of detecting anomalous command injection attempts. Monitor logs for suspicious WebSocket activity and unexpected command executions. Additionally, run the application with the least privileges necessary to limit the impact of potential exploitation. Regularly audit and update dependencies and maintain a robust patch management process to reduce exposure to similar vulnerabilities.