CVE-2018-7756
📋 TL;DR
CVE-2018-7756 is a critical vulnerability in DEWESoft X3 SP1 installer where the RunExeFile.exe component lacks authentication on TCP port 1999. This allows remote attackers to execute arbitrary code or access internal commands without credentials. Organizations using DEWESoft X3 SP1 (64-bit) devices are affected.
💻 Affected Systems
- DEWESoft X3 SP1 (64-bit)
📦 What is this software?
Dewesoft by Dewesoft
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise via remote code execution, allowing attackers to install malware, steal data, or pivot to other systems.
Likely Case
Remote attackers execute arbitrary commands to download and run malicious executables, potentially leading to ransomware deployment or data exfiltration.
If Mitigated
If properly segmented and firewalled, impact limited to isolated network segments with no internet exposure.
🎯 Exploit Status
Public exploit code available showing simple command execution via RUN and SETFIREWALL commands.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Update to DEWESoft X3 SP2 or later
Vendor Advisory: https://www.dewesoft.com/
Restart Required: Yes
Instructions:
1. Download latest DEWESoft X3 version from official vendor site. 2. Uninstall vulnerable version. 3. Install updated version. 4. Restart system.
🔧 Temporary Workarounds
Block Port 1999
windowsBlock inbound and outbound traffic on TCP port 1999 at network perimeter and host firewall.
netsh advfirewall firewall add rule name="Block DEWESoft Port 1999" dir=in action=block protocol=TCP localport=1999
netsh advfirewall firewall add rule name="Block DEWESoft Port 1999" dir=out action=block protocol=TCP localport=1999
Disable RunExeFile.exe Service
windowsStop and disable the vulnerable RunExeFile.exe service.
sc stop "DEWESoft RunExeFile Service"
sc config "DEWESoft RunExeFile Service" start= disabled
🧯 If You Can't Patch
- Segment affected devices in isolated network VLAN with strict access controls.
- Implement host-based firewall rules to only allow trusted IP addresses to connect to port 1999.
🔍 How to Verify
Check if Vulnerable:
Check if DEWESoft X3 SP1 (64-bit) is installed and if port 1999 is listening: netstat -an | findstr :1999Check Version:
Check DEWESoft version in Control Panel > Programs and Features or program installation directory.Verify Fix Applied:
Verify updated to X3 SP2 or later and port 1999 is no longer listening or requires authentication.📡 Detection & Monitoring
Log Indicators:
- Unexpected connections to port 1999
- Execution of RunExeFile.exe with network parameters
- Download of external executables via RUN commands
Network Indicators:
- TCP connections to port 1999 from untrusted sources
- Unusual outbound connections following port 1999 access
SIEM Query:
source_port=1999 OR dest_port=1999 OR process_name="RunExeFile.exe"