CVE-2024-38528
📋 TL;DR
CVE-2024-38528 is a denial-of-service vulnerability in ntpd-rs where an unauthenticated remote attacker can crash the service by exploiting missing connection limits for NTS-KE connections. Only systems with NTS-KE server configurations are affected - the default configuration is not vulnerable. This impacts organizations using ntpd-rs with NTS-KE enabled for time synchronization.
💻 Affected Systems
- ntpd-rs
⚠️ 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 service outage of time synchronization, potentially affecting system logging, authentication, and other time-dependent services across the network.
Likely Case
Service crash requiring manual restart of ntpd-rs, causing temporary loss of time synchronization until service is restored.
If Mitigated
No impact if NTS-KE is not configured or if the system is patched.
🎯 Exploit Status
Exploitation involves sending excessive NTS-KE connection requests to overwhelm the service.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.1.3
Vendor Advisory: https://github.com/pendulum-project/ntpd-rs/security/advisories/GHSA-2xpx-vcmq-5f72
Restart Required: Yes
Instructions:
1. Update ntpd-rs to version 1.1.3 or later using your package manager. 2. Restart the ntpd-rs service. 3. Verify the service is running with the patched version.
🔧 Temporary Workarounds
Disable NTS-KE Server
allRemove or comment out NTS-KE server configuration to eliminate the attack vector
Edit ntpd-rs configuration file and remove NTS-KE server settings
Restart ntpd-rs service
Network Access Control
linuxRestrict network access to ntpd-rs NTS-KE port (typically 4460)
iptables -A INPUT -p tcp --dport 4460 -j DROP
ufw deny 4460/tcp
🧯 If You Can't Patch
- Disable NTS-KE server functionality in configuration
- Implement network segmentation and firewall rules to restrict access to ntpd-rs NTS-KE port
🔍 How to Verify
Check if Vulnerable:
Check if ntpd-rs version is below 1.1.3 AND NTS-KE server is configured in /etc/ntpd-rs/ntp.toml or equivalent config fileCheck Version:
ntpd-rs --versionVerify Fix Applied:
Verify ntpd-rs version is 1.1.3 or higher and service is running normally📡 Detection & Monitoring
Log Indicators:
- Multiple connection attempts to NTS-KE port
- ntpd-rs service crash logs
- High number of failed NTS-KE handshakes
Network Indicators:
- Unusual traffic spikes to port 4460 (NTS-KE)
- Multiple TCP connections to NTS-KE port from single source
SIEM Query:
source="ntpd-rs" AND ("crash" OR "panic" OR "connection limit exceeded")