CVE-2020-5316
📋 TL;DR
This vulnerability allows a locally authenticated low-privileged user to load arbitrary DLLs through Dell SupportAssist, leading to privilege escalation and execution of arbitrary code with elevated privileges. It affects both business and home versions of Dell SupportAssist across multiple versions. The issue stems from an uncontrolled search path vulnerability (CWE-427).
💻 Affected Systems
- Dell SupportAssist for Business PCs
- Dell SupportAssist for Home PCs
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
An attacker with local low-privileged access could execute arbitrary code with SYSTEM/administrator privileges, potentially leading to full system compromise, data theft, or installation of persistent malware.
Likely Case
A malicious insider or compromised low-privileged account could escalate privileges to gain administrative control over the system, enabling further lateral movement or data access.
If Mitigated
With proper access controls and monitoring, impact is limited to the local system, though privilege escalation remains possible if exploited.
🎯 Exploit Status
Exploitation requires local authenticated access but is technically straightforward once access is obtained. No public exploit code is known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Update to Dell SupportAssist version 3.4.1 or later for Home PCs, and version 2.2 or later for Business PCs (check specific vendor advisory for exact versions).
Vendor Advisory: http://www.dell.com/support/article/SLN320101
Restart Required: Yes
Instructions:
1. Open Dell SupportAssist application. 2. Check for updates in settings. 3. If update available, download and install. 4. Alternatively, download latest version from Dell website. 5. Restart system after installation.
🔧 Temporary Workarounds
Remove vulnerable DLL search paths
windowsModify system PATH environment variable to remove insecure directories or restrict write permissions to directories where SupportAssist searches for DLLs.
Not applicable - requires manual configuration via System Properties > Advanced > Environment Variables
Uninstall SupportAssist
windowsCompletely remove Dell SupportAssist if not needed, eliminating the vulnerability.
Control Panel > Programs > Uninstall a program > Select Dell SupportAssist > Uninstall
🧯 If You Can't Patch
- Restrict local user access to systems with vulnerable SupportAssist versions
- Implement application whitelisting to prevent execution of unauthorized DLLs
🔍 How to Verify
Check if Vulnerable:
Check SupportAssist version: Open SupportAssist > Settings > About, or check Programs and Features in Control Panel for version number.Check Version:
wmic product where name="Dell SupportAssist" get versionVerify Fix Applied:
Verify version is 3.4.1 or later for Home PCs, or 2.2 or later for Business PCs. Test with non-admin account attempting DLL hijacking (in controlled environment).📡 Detection & Monitoring
Log Indicators:
- Windows Event Logs showing SupportAssist loading DLLs from unusual locations
- Security logs showing privilege escalation attempts
Network Indicators:
- Not applicable - local exploitation only
SIEM Query:
EventID=4688 AND ProcessName="SupportAssist*" AND CommandLine CONTAINS "dll" OR ParentProcessName="SupportAssist*" AND NewProcessName="cmd.exe"