CVE-2024-28751
📋 TL;DR
This vulnerability allows a high-privileged remote attacker to enable telnet access with hardcoded credentials on affected systems. Attackers can gain unauthorized access to devices, potentially leading to full system compromise. Organizations using the affected products with default configurations are at risk.
💻 Affected Systems
- Specific products not listed in provided references; consult VDE-2024-012 advisory for details
⚠️ 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
Complete system takeover with administrative privileges, data exfiltration, ransomware deployment, and persistent backdoor installation.
Likely Case
Unauthorized access to sensitive systems, credential harvesting, lateral movement within the network, and installation of malware.
If Mitigated
Limited impact due to network segmentation, strong authentication controls, and monitoring that detects unauthorized telnet access attempts.
🎯 Exploit Status
Exploitation requires initial high-privileged access, but the telnet enabling mechanism is straightforward once that access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Consult vendor advisory for specific patched versions
Vendor Advisory: https://cert.vde.com/en/advisories/VDE-2024-012
Restart Required: Yes
Instructions:
1. Identify affected products using VDE-2024-012 advisory
2. Contact vendor for specific patched firmware versions
3. Download and verify firmware integrity
4. Apply firmware update following vendor instructions
5. Restart affected devices
6. Verify telnet is disabled and hardcoded credentials are removed
🔧 Temporary Workarounds
Disable Telnet Service
linuxManually disable telnet service on affected devices to prevent exploitation
telnet service disable
systemctl disable telnet
chkconfig telnet off
Network Access Control
allBlock telnet port (23) at network perimeter and internally
iptables -A INPUT -p tcp --dport 23 -j DROP
firewall-cmd --permanent --add-port=23/tcp
firewall-cmd --permanent --remove-port=23/tcp
🧯 If You Can't Patch
- Implement strict network segmentation to isolate affected devices
- Deploy intrusion detection systems to monitor for telnet connection attempts and alert on unauthorized access
🔍 How to Verify
Check if Vulnerable:
Check if telnet service is enabled on port 23 and test authentication with known hardcoded credentials (consult VDE-2024-012 for specific credentials)Check Version:
Consult vendor documentation for device-specific version check commandsVerify Fix Applied:
Verify telnet service is disabled, port 23 is closed, and firmware version matches patched version from vendor📡 Detection & Monitoring
Log Indicators:
- Unexpected telnet service startup events
- Authentication attempts with hardcoded credentials
- Failed login attempts followed by successful telnet access
Network Indicators:
- Unexpected telnet traffic on port 23
- Telnet connections from unauthorized IP addresses
- Telnet sessions outside of maintenance windows
SIEM Query:
source="*telnet*" AND (event="service_start" OR event="authentication_success")