CVE-2019-0916
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on affected systems by exploiting a memory corruption flaw in the Chakra scripting engine in Microsoft Edge. Attackers can craft malicious web content that triggers the vulnerability when visited by users. All users running vulnerable versions of Microsoft Edge are affected.
💻 Affected Systems
- Microsoft Edge
📦 What is this software?
Chakracore by Microsoft
Edge by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control over the victim's computer, enabling data theft, ransomware deployment, or persistent backdoor installation.
Likely Case
Attackers deliver malware through compromised websites or malicious ads, leading to credential theft, banking fraud, or system disruption.
If Mitigated
With proper patching and security controls, impact is limited to potential browser crashes or denial of service.
🎯 Exploit Status
Requires user to visit malicious website or open malicious content. No authentication needed for exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Microsoft Edge version with April 2019 security updates
Vendor Advisory: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0916
Restart Required: Yes
Instructions:
1. Open Microsoft Edge. 2. Click Settings (three dots) > Help and feedback > About Microsoft Edge. 3. Allow browser to check for and install updates. 4. Restart browser when prompted. For enterprise: Deploy Windows Update KB4493509 or later through WSUS/SCCM.
🔧 Temporary Workarounds
Disable JavaScript
windowsTemporarily disable JavaScript in Microsoft Edge to prevent exploitation
edge://settings/content/javascript
Use Alternative Browser
windowsSwitch to Internet Explorer or another browser until Edge is patched
🧯 If You Can't Patch
- Implement web filtering to block known malicious sites and restrict access to untrusted websites
- Enable Enhanced Protected Mode in Edge settings and use application whitelisting
🔍 How to Verify
Check if Vulnerable:
Check Edge version: Open Edge > Settings > About Microsoft Edge. If version is older than April 2019 updates, system is vulnerable.Check Version:
In Edge browser, navigate to edge://version/Verify Fix Applied:
Verify Edge version is updated to include April 2019 security patches. Check Windows Update history for KB4493509 or later.📡 Detection & Monitoring
Log Indicators:
- Edge crash reports with memory access violations
- Unexpected Edge process termination
- Security event logs showing suspicious script execution
Network Indicators:
- Outbound connections from Edge to unknown IPs following browser crashes
- Unusual DNS queries from Edge process
SIEM Query:
EventID=1000 OR EventID=1001 Source='Microsoft-Windows-WER-SystemErrorReporting' AND ApplicationName='MicrosoftEdge.exe'