CVE-2019-1175
📋 TL;DR
CVE-2019-1175 is a local privilege escalation vulnerability in Microsoft's psmsrv.dll component. An authenticated attacker could exploit this to execute arbitrary code with elevated system permissions. This affects Windows systems where an attacker has local access.
💻 Affected Systems
- Microsoft Windows
📦 What is this software?
Windows 10 by Microsoft
Windows 10 by Microsoft
Windows 10 by Microsoft
Windows 10 by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
An attacker gains full SYSTEM privileges, enabling complete system compromise, persistence installation, credential theft, and lateral movement across the network.
Likely Case
Malware or malicious users escalate privileges from standard user to SYSTEM to bypass security controls, install backdoors, or disable security software.
If Mitigated
With proper patching and least privilege principles, impact is limited to isolated systems with no administrative access available to attackers.
🎯 Exploit Status
Exploitation requires local access and authentication. Multiple security researchers have published proof-of-concept code.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Security updates from August 2019 (KB4512508 for 1803, KB4511553 for 1809, KB4512501 for 1903)
Vendor Advisory: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1175
Restart Required: Yes
Instructions:
1. Apply Windows Update from August 2019 or later. 2. Install the specific KB patch for your Windows version. 3. Restart the system to complete installation.
🔧 Temporary Workarounds
Restrict local user privileges
windowsImplement least privilege by removing administrative rights from standard users
Application control policies
windowsUse AppLocker or Windows Defender Application Control to block unauthorized applications
🧯 If You Can't Patch
- Implement strict application whitelisting to prevent execution of unauthorized binaries
- Segment networks to limit lateral movement from potentially compromised systems
🔍 How to Verify
Check if Vulnerable:
Check Windows Update history for August 2019 security patches or run: wmic qfe list | findstr "4512508 4511553 4512501"Check Version:
winver or systeminfo | findstr /B /C:"OS Name" /C:"OS Version"Verify Fix Applied:
Verify the patch is installed via: Get-Hotfix -Id KB4512508, KB4511553, or KB4512501 (depending on Windows version)📡 Detection & Monitoring
Log Indicators:
- Event ID 4688 with unusual parent processes spawning with SYSTEM privileges
- Unexpected elevation of process privileges in security logs
Network Indicators:
- Unusual outbound connections from systems after privilege escalation
SIEM Query:
source="windows_security" event_id=4688 AND (process_name="*" AND integrity_level="System") AND parent_process_name NOT IN ("services.exe", "wininit.exe")