CVE-2023-45312
📋 TL;DR
CVE-2023-45312 is an authentication bypass vulnerability in mtproto_proxy (MTProto proxy) for Erlang that allows unauthenticated remote attackers to execute arbitrary commands. This affects default installations of mtproto_proxy up to version 0.7.2. Organizations running vulnerable MTProxy servers for Telegram are at risk.
💻 Affected Systems
- mtproto_proxy (MTProto proxy)
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with attacker gaining full control over the proxy server, potentially pivoting to internal networks, stealing sensitive data, and deploying ransomware or other malware.
Likely Case
Remote command execution leading to proxy server takeover, data exfiltration, and use of compromised server for further attacks or cryptocurrency mining.
If Mitigated
Limited impact with proper network segmentation and authentication controls preventing exploitation or containing damage to isolated proxy environment.
🎯 Exploit Status
Exploitation requires no authentication and has been publicly documented with technical details available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 0.7.3 or later
Vendor Advisory: https://github.com/seriyps/mtproto_proxy
Restart Required: Yes
Instructions:
1. Update mtproto_proxy to version 0.7.3 or later using package manager or source compilation. 2. Restart the mtproto_proxy service. 3. Verify the update was successful.
🔧 Temporary Workarounds
Network Access Restriction
linuxRestrict network access to mtproto_proxy using firewall rules to only allow trusted IP addresses
iptables -A INPUT -p tcp --dport 443 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP
Service Isolation
linuxRun mtproto_proxy in a container or isolated environment with minimal privileges
docker run -d --name mtproxy --restart always -p 443:443 seriyps/mtproto_proxy:latest
🧯 If You Can't Patch
- Implement strict network segmentation to isolate vulnerable proxy servers from critical infrastructure
- Deploy intrusion detection systems to monitor for exploitation attempts and command execution patterns
🔍 How to Verify
Check if Vulnerable:
Check mtproto_proxy version: grep -i version /path/to/mtproto_proxy/config or check running process versionCheck Version:
mtproto_proxy --version or check package manager: dpkg -l | grep mtproto-proxyVerify Fix Applied:
Verify version is 0.7.3 or later and test authentication requirements for proxy access📡 Detection & Monitoring
Log Indicators:
- Unauthenticated access attempts to proxy endpoints
- Unusual command execution patterns in system logs
- New process creation from mtproto_proxy user
Network Indicators:
- Unusual outbound connections from proxy server
- Command and control traffic patterns
- Exploitation attempts on proxy port 443
SIEM Query:
source="mtproto_proxy.log" AND (event="unauthorized_access" OR event="command_execution")