CVE-2023-53817
📋 TL;DR
A NULL pointer dereference vulnerability in the Linux kernel's mpi_cmp_ui() function allows remote attackers to trigger a kernel panic (denial of service) during NVMeTCP authentication. This affects systems using NVMe over TCP with Diffie-Hellman authentication. Attackers can exploit this by sending specially crafted authentication requests.
💻 Affected Systems
- Linux Kernel
⚠️ 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
Kernel panic leading to system crash and denial of service, potentially disrupting critical services.
Likely Case
Remote denial of service attack causing system instability or crashes in NVMeTCP environments.
If Mitigated
Limited impact if NVMeTCP authentication is disabled or systems are not exposed to untrusted networks.
🎯 Exploit Status
Exploitation requires ability to initiate NVMeTCP authentication with specific DH parameters. No public exploit code known at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Multiple stable kernel versions with commits: 0fc7147c6943, 12ac013ad7ff, 61f5453e9706, 67589d247909, 9e47a758b701
Vendor Advisory: https://git.kernel.org/stable/c/0fc7147c694394f8a8cbc19570c6bc918cac0906
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution vendor. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable NVMeTCP Authentication
linuxDisable Diffie-Hellman authentication for NVMe over TCP if not required
# Configure NVMeTCP to disable authentication in your NVMe configuration
Network Segmentation
linuxRestrict access to NVMeTCP ports to trusted networks only
iptables -A INPUT -p tcp --dport 4420 -s trusted_network -j ACCEPT
iptables -A INPUT -p tcp --dport 4420 -j DROP
🧯 If You Can't Patch
- Implement strict network access controls to limit NVMeTCP port (typically 4420) exposure
- Monitor systems for kernel panic events and unauthorized authentication attempts
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if NVMeTCP with DH authentication is enabled. Vulnerable if using unpatched kernel with NVMeTCP authentication.Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated to include one of the fix commits. Check dmesg for kernel panic events related to mpi_cmp_ui.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in dmesg or syslog
- NULL pointer dereference errors mentioning mpi_cmp_ui
- NVMeTCP authentication failures
Network Indicators:
- Unexpected authentication attempts on NVMeTCP port 4420
- Traffic patterns suggesting DH parameter manipulation
SIEM Query:
source="kernel" AND ("panic" OR "NULL pointer dereference" OR "mpi_cmp_ui")🔗 References
- https://git.kernel.org/stable/c/0fc7147c694394f8a8cbc19570c6bc918cac0906
- https://git.kernel.org/stable/c/12ac013ad7ff0df066451e825801d805095b3776
- https://git.kernel.org/stable/c/61f5453e9706e99713825594e0c8f9031485fb5f
- https://git.kernel.org/stable/c/67589d247909043e94d2dd5fb590958e0f99d58d
- https://git.kernel.org/stable/c/9e47a758b70167c9301d2b44d2569f86c7796f2d
- https://git.kernel.org/stable/c/ae63e84ffda74267bf7277c38415ba38389229a0
- https://git.kernel.org/stable/c/d3ad023a39f1127dcfd331c562673355dc078650
- https://git.kernel.org/stable/c/fde791e8a96a64ea7b0ad2440e43586447a209c6
