CVE-2023-43694
📋 TL;DR
An out-of-bounds read vulnerability in Malwarebytes disassembling utilities can cause application crashes and denial of service. This affects Malwarebytes consumer and business editions, potentially disrupting security protection on vulnerable systems.
💻 Affected Systems
- Malwarebytes
- Malwarebytes Nebula
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Malwarebytes service crashes repeatedly, leaving system unprotected while requiring manual intervention to restore functionality.
Likely Case
Application instability or crashes when processing specially crafted files during scanning operations.
If Mitigated
Minor performance impact or isolated crashes that don't affect overall system stability.
🎯 Exploit Status
Requires ability to place malicious file on target system and trigger scanning.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Malwarebytes 4.6.15+ or 5.1.6+; Nebula updates via vendor
Vendor Advisory: https://www.malwarebytes.com/secure/cves/cve-2023-43694
Restart Required: No
Instructions:
1. Open Malwarebytes application. 2. Click Settings > About. 3. Check for updates. 4. Install available updates. 5. For Nebula, update through management console.
🔧 Temporary Workarounds
Disable real-time scanning temporarily
allTemporarily disable real-time protection to prevent crashes while maintaining manual scanning capability
🧯 If You Can't Patch
- Implement application whitelisting to prevent execution of untrusted files
- Use network segmentation to limit exposure of vulnerable endpoints
🔍 How to Verify
Check if Vulnerable:
Check Malwarebytes version in Settings > About. If version is 4.6.14.326 or earlier, or 5.1.5.116 or earlier, system is vulnerable.Check Version:
On Windows: wmic product where name='Malwarebytes' get versionVerify Fix Applied:
Verify version is 4.6.15+ or 5.1.6+ after update. Test scanning functionality with various file types.📡 Detection & Monitoring
Log Indicators:
- Application crash logs from Malwarebytes service
- Unexpected service restarts in Windows Event Logs
Network Indicators:
- None - local vulnerability only
SIEM Query:
EventID=1000 OR EventID=1001 AND Source='Malwarebytes' AND Keywords='Crash'