CVE-2026-27182: Saturn Remote Mouse Server RCE Vulnerability

CVE-2026-27182 Overview

Saturn Remote Mouse Server contains a command injection vulnerability that allows unauthenticated attackers to execute arbitrary commands by sending specially crafted UDP JSON frames to port 27000. Attackers on the local network can send malformed packets with unsanitized command data that the service forwards directly to OS execution functions, enabling remote code execution under the service account.

Critical Impact

Unauthenticated attackers on the local network can achieve remote code execution by exploiting the UDP-based command injection, potentially gaining full control of systems running the vulnerable Saturn Remote Mouse Server service.

Affected Products

• Saturn Remote Mouse Server (affected versions not specified in advisory)

Discovery Timeline

• 2026-02-18 - CVE-2026-27182 published to NVD
• 2026-02-19 - Last updated in NVD database

Technical Details for CVE-2026-27182

Vulnerability Analysis

This vulnerability is classified under CWE-306 (Missing Authentication for Critical Function), indicating that the Saturn Remote Mouse Server fails to implement proper authentication checks before processing incoming UDP commands. The service listens on UDP port 27000 and accepts JSON-formatted frames without validating the source or requiring any form of authentication. When a specially crafted JSON payload is received, the server processes the command data and passes it directly to operating system execution functions without proper input sanitization.

The lack of authentication combined with insufficient input validation creates a critical attack surface. An adversary positioned on the same local network can construct malicious UDP packets containing shell commands embedded within the JSON structure. Because the server processes these commands at the privilege level of the service account, successful exploitation can result in complete system compromise.

Root Cause

The root cause of this vulnerability is twofold: the absence of authentication mechanisms for the UDP listener service and the direct execution of user-controlled input through OS command execution functions. The application accepts and processes commands from any source on the network without verifying the legitimacy of the request, violating fundamental security principles of authentication before action and input validation before execution.

Attack Vector

The attack leverages the local network to reach the vulnerable UDP service on port 27000. An attacker must be on the same network segment as the target system running Saturn Remote Mouse Server. The attack flow involves:

1. Identifying systems with Saturn Remote Mouse Server running and port 27000 open
2. Crafting a malicious UDP JSON frame containing command injection payloads
3. Sending the frame to the target on port 27000
4. The server processes the JSON without authentication and executes the embedded commands
5. Arbitrary commands execute under the service account context

For detailed technical information, refer to the VulnCheck Advisory and the Packet Storm release.

Detection Methods for CVE-2026-27182

Indicators of Compromise

• Unexpected UDP traffic to port 27000 from systems that should not be communicating with the Saturn Remote Mouse Server
• Anomalous process spawning from the Saturn Remote Mouse Server service process
• Command-line execution patterns consistent with shell injection (e.g., command chaining characters, encoded payloads)
• Network connections or child processes initiated by the service account that deviate from normal behavior

Detection Strategies

• Implement network monitoring rules to detect and alert on UDP traffic to port 27000, especially from unauthorized sources
• Deploy endpoint detection and response (EDR) solutions to monitor for suspicious process trees originating from the Saturn Remote Mouse Server executable
• Configure host-based intrusion detection to flag command execution patterns indicative of injection attacks
• Utilize SentinelOne's behavioral AI to detect anomalous execution chains spawned by network-facing services

Monitoring Recommendations

• Enable verbose logging for the Saturn Remote Mouse Server service if supported by the application
• Monitor system event logs for unusual process creation events under the service account
• Implement network segmentation logging to track cross-segment communication attempts targeting port 27000
• Set up alerts for any shell interpreter invocations (cmd.exe, powershell.exe, /bin/sh, /bin/bash) spawned as children of the remote mouse service

How to Mitigate CVE-2026-27182

Immediate Actions Required

• Disable or uninstall Saturn Remote Mouse Server on systems where it is not strictly required
• Block UDP port 27000 at the host firewall level to prevent external access to the vulnerable service
• Implement network segmentation to isolate systems running the vulnerable software from untrusted network segments
• Monitor for exploitation attempts using the detection strategies outlined above

Patch Information

At the time of publication, no vendor patch information is available in the advisory data. System administrators should monitor the Saturn Remote official website for security updates and apply patches as soon as they become available. Additionally, review the VulnCheck Advisory for the latest remediation guidance.

Workarounds

• Configure host-based firewalls to block inbound UDP traffic on port 27000 from all sources except explicitly trusted management systems
• Run the Saturn Remote Mouse Server under a low-privilege service account to limit the impact of successful exploitation
• Consider alternative remote input solutions that implement proper authentication and encryption
• If the service must remain operational, deploy network access controls to restrict which systems can communicate with the service

# Example: Block UDP port 27000 on Windows Firewall
netsh advfirewall firewall add rule name="Block Saturn Remote UDP 27000" dir=in action=block protocol=UDP localport=27000

# Example: Block UDP port 27000 on Linux iptables
iptables -A INPUT -p udp --dport 27000 -j DROP