CVE-2018-8726
📋 TL;DR
CVE-2018-8726 is a buffer overflow vulnerability in K7Antivirus Premium's K7TSMngr.exe component that allows local attackers to execute arbitrary code with system privileges. This affects users running K7Antivirus Premium 15.1.0.53 on Windows systems. The vulnerability requires local access to the system to exploit.
💻 Affected Systems
- K7Antivirus Premium
📦 What is this software?
Antivrius by K7computing
Enterprise Security by K7computing
Total Security by K7computing
Ultimate Security by K7computing
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with SYSTEM/administrator privileges, allowing installation of persistent malware, data theft, and lateral movement within the network.
Likely Case
Local privilege escalation from a lower-privileged user account to SYSTEM/administrator level, enabling further malicious activities on the compromised host.
If Mitigated
Limited impact if proper endpoint security controls, least privilege principles, and network segmentation are implemented.
🎯 Exploit Status
Exploitation requires local access to the system. Buffer overflow vulnerabilities in security software components are often targeted due to their high privileges.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Versions after 15.1.0.53
Vendor Advisory: https://support.k7computing.com/index.php?/selfhelp/view-article/Advisory-issued-on-6th-January-2021
Restart Required: Yes
Instructions:
1. Open K7Antivirus Premium. 2. Click on 'Update' or 'Check for Updates'. 3. Install all available updates. 4. Restart the computer to ensure the patch is fully applied.
🔧 Temporary Workarounds
Disable vulnerable service
windowsTemporarily disable the K7TSMngr.exe service to prevent exploitation while awaiting patch deployment
sc stop K7TSMngr
sc config K7TSMngr start= disabled
🧯 If You Can't Patch
- Implement strict least privilege principles - ensure no users have administrative rights unnecessarily
- Deploy application whitelisting to prevent execution of unauthorized binaries and scripts
🔍 How to Verify
Check if Vulnerable:
Check K7Antivirus Premium version in the application interface or via 'About' section. If version is 15.1.0.53, the system is vulnerable.Check Version:
wmic product where "name like 'K7Antivirus%'" get versionVerify Fix Applied:
Verify K7Antivirus Premium version is greater than 15.1.0.53 and check that K7TSMngr.exe service is running the updated version.📡 Detection & Monitoring
Log Indicators:
- Unusual process creation from K7TSMngr.exe
- Access violations or buffer overflow errors in K7Antivirus logs
- Multiple failed privilege escalation attempts
Network Indicators:
- Unusual outbound connections from K7TSMngr.exe process
- Lateral movement attempts from previously compromised hosts
SIEM Query:
Process Creation where (Image contains 'K7TSMngr.exe' AND ParentImage not contains 'K7') OR (Process Creation where ParentImage contains 'K7TSMngr.exe')