CVE-2025-66576 is an OS command injection vulnerability classified under CWE-78 affecting Remotecontrolio's Remote Keyboard Desktop version 1.0.1. The vulnerability arises because the software improperly neutralizes special characters in inputs passed to the Windows rundll32.exe utility, which is used to execute DLL functions. Attackers can exploit this flaw remotely without authentication or user interaction by crafting malicious requests that invoke the vulnerable exported function. This leads to arbitrary system command execution with the privileges of the application, potentially allowing full system compromise. The CVSS 4.0 score of 8.9 reflects its high impact and ease of exploitation. No patches or mitigations have been officially released yet, and no known exploits are currently observed in the wild. The vulnerability affects the confidentiality, integrity, and availability of systems running the affected software. Given the nature of Remote Keyboard Desktop as a remote access tool, exploitation could facilitate lateral movement, data exfiltration, or ransomware deployment. The lack of authentication and user interaction requirements significantly increases the attack surface. The vulnerability is particularly critical in enterprise environments where remote desktop tools are widely used for remote administration and support.

For European organizations, this vulnerability presents a serious risk of unauthorized remote code execution, potentially leading to full system compromise. Attackers could leverage this flaw to gain persistent access, steal sensitive data, disrupt operations, or deploy malware such as ransomware. Organizations in sectors with high reliance on remote desktop solutions, including finance, healthcare, government, and critical infrastructure, are especially vulnerable. The ability to exploit the vulnerability without authentication or user interaction increases the likelihood of automated attacks and worm-like propagation within networks. This could result in widespread operational disruption and significant financial and reputational damage. Additionally, the vulnerability could be exploited for espionage or sabotage, particularly in countries with heightened geopolitical tensions. The absence of patches means organizations must rely on interim mitigations, increasing operational complexity and risk exposure.

1. Immediately isolate and restrict network access to systems running Remote Keyboard Desktop 1.0.1, limiting exposure to untrusted networks. 2. Disable or uninstall Remote Keyboard Desktop where feasible until a patch is available. 3. Monitor network traffic and system logs for unusual rundll32.exe invocations or suspicious command execution patterns. 4. Implement strict firewall rules to block inbound connections targeting the vulnerable service ports. 5. Employ application whitelisting to prevent unauthorized execution of rundll32.exe with unexpected parameters. 6. Use endpoint detection and response (EDR) tools to detect and respond to anomalous behaviors indicative of exploitation attempts. 7. Educate IT staff about the vulnerability and ensure rapid incident response readiness. 8. Follow vendor communications closely for patch releases and apply updates promptly once available. 9. Consider deploying network intrusion detection/prevention systems (IDS/IPS) with signatures tuned to detect exploitation attempts. 10. Conduct thorough security assessments to identify any signs of compromise related to this vulnerability.