CVE-2023-0383
📋 TL;DR
This vulnerability in M-Files Server allows attackers to cause denial of service through uncontrolled memory consumption. By sending specially crafted user-controlled operations, attackers can exhaust server memory, causing service disruption. All M-Files Server installations before version 23.4.12528.1 are affected.
💻 Affected Systems
- M-Files Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete service outage of M-Files Server, potentially affecting all document management and business processes dependent on the system.
Likely Case
Service degradation or temporary unavailability of M-Files Server, disrupting document access and workflow processes.
If Mitigated
Minimal impact with proper memory monitoring and rate limiting in place, though some performance degradation may occur during attack attempts.
🎯 Exploit Status
The vulnerability requires sending crafted operations to the server, which is straightforward for attackers with network access to the service.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 23.4.12528.1 and later
Vendor Advisory: https://empower.m-files.com/security-advisories/CVE-2023-0383
Restart Required: Yes
Instructions:
1. Download M-Files Server version 23.4.12528.1 or later from the M-Files customer portal. 2. Backup your M-Files Server configuration and databases. 3. Run the installer with administrative privileges. 4. Follow the upgrade wizard. 5. Restart the M-Files Server service after installation completes.
🔧 Temporary Workarounds
Network Access Restriction
windowsRestrict network access to M-Files Server to only trusted IP addresses and networks.
Use Windows Firewall or network firewall rules to limit access to M-Files Server ports (typically 2266, 2267, 2268)
Memory Monitoring and Alerting
windowsImplement aggressive memory monitoring and alerting to detect potential exploitation attempts.
Configure Windows Performance Monitor to track M-Files Server process memory usage and set alerts for abnormal consumption patterns
🧯 If You Can't Patch
- Implement strict network segmentation and firewall rules to limit access to M-Files Server
- Deploy rate limiting and request filtering at the network perimeter or load balancer
🔍 How to Verify
Check if Vulnerable:
Check M-Files Server version in the M-Files Admin tool under Help > About, or check the installed version in Windows Programs and Features.Check Version:
In M-Files Admin: Help > About, or PowerShell: Get-WmiObject -Class Win32_Product | Where-Object {$_.Name -like '*M-Files Server*'} | Select-Object Name, VersionVerify Fix Applied:
Verify the version is 23.4.12528.1 or later in M-Files Admin tool or Windows Programs and Features.📡 Detection & Monitoring
Log Indicators:
- Rapid increase in memory usage in Windows Event Logs
- M-Files Server service crashes or restarts in Application logs
- Unusual patterns of user operations in M-Files audit logs
Network Indicators:
- Unusual volume of requests to M-Files Server API endpoints
- Requests with abnormal payload sizes or patterns
SIEM Query:
source="windows" AND (event_id=1000 OR event_id=1001) AND process_name="M-Files Server.exe" OR source="m-files" AND (message="*memory*" OR message="*crash*" OR message="*restart*")