CVE-2019-0655
📋 TL;DR
This is a remote code execution vulnerability in Microsoft Edge's scripting engine that allows attackers to execute arbitrary code on affected systems. It affects users running vulnerable versions of Microsoft Edge on Windows systems. Attackers can exploit this by tricking users into visiting malicious websites.
💻 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 machine, enabling data theft, ransomware deployment, or persistent backdoor installation.
Likely Case
Malicious code execution in the context of the current user, potentially leading to credential theft, data exfiltration, or installation of additional malware.
If Mitigated
No impact if patched or if security controls block malicious websites and scripts.
🎯 Exploit Status
Exploitation requires user interaction (visiting malicious website) but no authentication. Memory corruption vulnerabilities in browsers are frequently exploited in the wild.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Microsoft Edge version with February 2019 security updates
Vendor Advisory: https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0655
Restart Required: Yes
Instructions:
1. Open Windows Update settings. 2. Check for updates. 3. Install all available updates, particularly the February 2019 security updates. 4. Restart the system when prompted.
🔧 Temporary Workarounds
Disable JavaScript
windowsDisable JavaScript in Microsoft Edge to prevent exploitation of scripting engine vulnerabilities
edge://settings/content/javascript (set to 'Block')
Use Enhanced Security Configuration
windowsEnable Enhanced Security Configuration in Internet Explorer mode settings for higher security
edge://settings/privacy (enable 'Enhanced security')
🧯 If You Can't Patch
- Migrate to Chromium-based Microsoft Edge which is not affected by this vulnerability
- Implement web filtering to block known malicious websites and restrict browsing to trusted sites only
🔍 How to Verify
Check if Vulnerable:
Check Edge version by navigating to edge://settings/help and verify if version is prior to February 2019 updatesCheck Version:
In Edge browser, navigate to edge://settings/help or check Windows Update history for February 2019 security updatesVerify Fix Applied:
Verify Edge version is updated to February 2019 or later security update version📡 Detection & Monitoring
Log Indicators:
- Edge crash reports with memory corruption signatures
- Unexpected process creation from Edge browser
- Suspicious network connections from Edge to unknown domains
Network Indicators:
- Traffic to known exploit kit domains
- Unexpected outbound connections following Edge usage
- Malicious script downloads
SIEM Query:
source="Microsoft-Windows-Security-Mitigations" AND event_id="1" AND process_name="MicrosoftEdge.exe" AND (memory_corruption OR access_violation)