CVE-2019-1092
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on affected systems by exploiting a memory corruption flaw in Microsoft Edge's Chakra JavaScript engine. Attackers can craft malicious web content that triggers the vulnerability when visited by users. This affects users running vulnerable versions of Microsoft Edge on Windows systems.
💻 Affected Systems
- Microsoft Edge
📦 What is this software?
Chakracore by Microsoft
Edge by Microsoft
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to install programs, view/change/delete data, or create new accounts with full user rights.
Likely Case
Attackers execute malicious code in the context of the current user, potentially leading to data theft, ransomware deployment, or lateral movement within networks.
If Mitigated
With proper security controls, exploitation attempts are blocked by security software or sandboxing, limiting impact to the browser sandbox.
🎯 Exploit Status
Exploitation requires user interaction (visiting malicious website), but no authentication is needed. Memory corruption vulnerabilities in JavaScript engines are commonly exploited in the wild.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: July 9, 2019 security update (KB4507453 for Windows 10 1903)
Vendor Advisory: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-1092
Restart Required: Yes
Instructions:
1. Open Windows Update settings. 2. Click 'Check for updates'. 3. Install the July 2019 cumulative security update. 4. Restart the computer when prompted.
🔧 Temporary Workarounds
Disable JavaScript
windowsDisable JavaScript in Microsoft Edge to prevent exploitation of the Chakra engine vulnerability
Use Enhanced Protected Mode
windowsEnable Enhanced Protected Mode in Internet Explorer settings (affects Edge compatibility mode)
🧯 If You Can't Patch
- Migrate to Chromium-based Microsoft Edge which is not affected by this vulnerability
- Implement application whitelisting to prevent execution of unauthorized code
🔍 How to Verify
Check if Vulnerable:
Check Microsoft Edge version by navigating to edge://settings/help and verify it's older than the July 2019 updateCheck Version:
wmic datafile where name="C:\\Windows\\SystemApps\\Microsoft.MicrosoftEdge_8wekyb3d8bbwe\\MicrosoftEdge.exe" get versionVerify Fix Applied:
Verify Windows Update history shows KB4507453 (or equivalent for your Windows version) installed, and Edge version shows July 2019 or later build📡 Detection & Monitoring
Log Indicators:
- Edge crash reports with memory access violations
- Unexpected process creation from Edge
- JavaScript engine error events
Network Indicators:
- Connections to suspicious domains from Edge process
- Unusual outbound traffic patterns
SIEM Query:
Process Creation where (Image contains "MicrosoftEdge" OR ParentImage contains "MicrosoftEdge") AND CommandLine contains suspicious patterns