CVE-2020-24576
📋 TL;DR
This vulnerability in Netskope Client allows low-privileged users to escalate their privileges to SYSTEM level on Windows systems. It affects Netskope Client versions through 77, enabling attackers with initial access to gain complete control over affected endpoints. Organizations using vulnerable Netskope Client versions are at risk of privilege escalation attacks.
💻 Affected Systems
- Netskope Client
📦 What is this software?
Netskope by Netskope
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with SYSTEM privileges, allowing attackers to install persistent malware, steal credentials, disable security controls, and pivot to other systems in the network.
Likely Case
Privilege escalation from standard user accounts to SYSTEM, enabling installation of additional malware, credential harvesting, and lateral movement within the network.
If Mitigated
Limited impact if proper endpoint security controls, least privilege principles, and network segmentation are implemented, though the vulnerability still provides a foothold for attackers.
🎯 Exploit Status
Exploitation requires local access with low-privileged user account. The vulnerability is in the client software's privilege handling mechanisms.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 78 and later
Vendor Advisory: https://www.netskope.com/company/security-compliance-and-assurance/release-78-security-advisory-nskpsa2020-001
Restart Required: Yes
Instructions:
1. Download Netskope Client version 78 or later from the Netskope portal. 2. Deploy the updated client to all affected endpoints. 3. Restart systems to complete the installation. 4. Verify the update was successful by checking the client version.
🔧 Temporary Workarounds
Restrict Local User Privileges
windowsImplement strict least privilege principles to limit what low-privileged users can do on systems.
Endpoint Security Controls
allDeploy endpoint detection and response (EDR) solutions to detect and block privilege escalation attempts.
🧯 If You Can't Patch
- Implement strict application control policies to prevent unauthorized privilege escalation attempts
- Deploy network segmentation to limit lateral movement from compromised endpoints
🔍 How to Verify
Check if Vulnerable:
Check Netskope Client version in the system tray or program files. Versions 77 and earlier are vulnerable.Check Version:
Check Netskope Client GUI or navigate to C:\Program Files\Netskope\STAgent and check file propertiesVerify Fix Applied:
Verify Netskope Client version is 78 or later. Check that the client is running properly without errors.📡 Detection & Monitoring
Log Indicators:
- Windows Event Logs showing privilege escalation attempts
- Netskope Client logs showing abnormal behavior
- Security logs with SYSTEM privilege acquisition from user accounts
Network Indicators:
- Unusual outbound connections from systems after privilege escalation
- Lateral movement attempts from affected endpoints
SIEM Query:
EventID=4688 AND NewProcessName LIKE '%netskope%' AND SubjectUserName NOT LIKE '%SYSTEM%' AND NewProcessName LIKE '%SYSTEM%'