CVE-2020-0768
📋 TL;DR
This is a remote code execution vulnerability in Microsoft browser scripting engines that allows attackers to execute arbitrary code on affected systems. It affects users of Microsoft Edge and Internet Explorer browsers. Successful exploitation could lead to complete system compromise.
💻 Affected Systems
- Microsoft Edge
- Internet Explorer
📦 What is this software?
Chakracore by Microsoft
Edge by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Complete system takeover with attacker gaining full control over the victim's machine, potentially leading to data theft, ransomware deployment, or lateral movement within networks.
Likely Case
Malicious website or advertisement executes code in browser context, potentially stealing credentials, session cookies, or installing malware on the victim's system.
If Mitigated
With proper patching and security controls, impact is limited to browser crashes or denial of service at worst.
🎯 Exploit Status
Exploitation requires user interaction (visiting malicious website or opening malicious document), but no authentication is needed. Memory corruption vulnerabilities in scripting engines are frequently exploited in the wild.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: March 2020 security updates for affected Windows versions
Vendor Advisory: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0768
Restart Required: Yes
Instructions:
1. Apply March 2020 security updates from Windows Update. 2. For enterprise environments, deploy updates through WSUS or SCCM. 3. Restart systems after update installation.
🔧 Temporary Workarounds
Disable scripting in Internet Explorer
windowsConfigure Internet Explorer to disable scripting, which prevents exploitation but breaks many websites
Internet Options → Security tab → Custom level → Disable Active Scripting
Use alternative browser
allSwitch to Chromium-based Microsoft Edge or other modern browsers not affected by this vulnerability
🧯 If You Can't Patch
- Implement application whitelisting to prevent unauthorized code execution
- Deploy network filtering to block access to known malicious websites and restrict browser internet access
🔍 How to Verify
Check if Vulnerable:
Check Windows Update history for March 2020 security updates or verify browser versions against patched versionsCheck Version:
wmic qfe list | findstr KB4550929 KB4550930 KB4550922 KB4550927Verify Fix Applied:
Verify KB4550929 (Windows 10 1903/1909), KB4550930 (Windows 10 1809), or other March 2020 security updates are installed📡 Detection & Monitoring
Log Indicators:
- Browser crash events in Windows Event Logs
- Unexpected process creation from browser processes
- Memory access violations in application logs
Network Indicators:
- Unusual outbound connections from browser processes
- Traffic to known exploit hosting domains
SIEM Query:
source="Windows Security" EventCode=4688 NewProcessName="*powershell*" OR NewProcessName="*cmd*" ParentProcessName="*iexplore*" OR ParentProcessName="*msedge*"