CVE-2023-53611
📋 TL;DR
This is a memory leak vulnerability in the Linux kernel's IPMI subsystem driver (ipmi_si). When try_smi_init() fails during initialization, it doesn't properly free allocated memory, causing kernel memory exhaustion over time. This affects Linux systems using the IPMI driver, particularly servers with BMC/IPMI hardware.
💻 Affected Systems
- Linux kernel
⚠️ Risk & Real-World Impact
Worst Case
Sustained exploitation could lead to kernel memory exhaustion, causing system instability, crashes, or denial of service requiring physical reboot.
Likely Case
Gradual memory consumption leading to performance degradation and eventual system instability when IPMI driver initialization fails repeatedly.
If Mitigated
Minimal impact with proper monitoring and memory limits; system remains functional but may experience performance issues.
🎯 Exploit Status
Requires ability to trigger IPMI driver initialization failures; memory leak occurs gradually over time rather than immediate exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits 09cb2a71b2e9, 1bfcfea0fae0, 5c5f02e16b91, 6cf1a126de29, or 7291af9a738d
Vendor Advisory: https://git.kernel.org/stable/c/09cb2a71b2e982015fe0464f28da1ab42b8e6375
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution vendor. 2. Reboot system to load new kernel. 3. Verify ipmi_si module loads correctly.
🔧 Temporary Workarounds
Disable IPMI driver
linuxPrevent loading of vulnerable ipmi_si module if IPMI functionality not required
echo 'blacklist ipmi_si' > /etc/modprobe.d/blacklist-ipmi.conf
rmmod ipmi_si
Limit module loading
linuxRestrict module loading to prevent accidental ipmi_si initialization
echo 'install ipmi_si /bin/false' >> /etc/modprobe.d/disable-ipmi.conf
🧯 If You Can't Patch
- Monitor kernel memory usage and system logs for memory leak indicators
- Implement strict access controls to IPMI/BMC interfaces and local system access
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if ipmi_si module is loaded: lsmod | grep ipmi_si && uname -rCheck Version:
uname -rVerify Fix Applied:
Verify kernel version is patched and monitor for memory leaks after IPMI operations📡 Detection & Monitoring
Log Indicators:
- Kernel oom-killer messages
- Memory allocation failures in dmesg
- IPMI initialization errors
Network Indicators:
- Unusual IPMI/BMC traffic patterns
SIEM Query:
source="kernel" AND ("oom-killer" OR "ipmi_si" OR "memory allocation failure")🔗 References
- https://git.kernel.org/stable/c/09cb2a71b2e982015fe0464f28da1ab42b8e6375
- https://git.kernel.org/stable/c/1bfcfea0fae0d0a6c6ff5543e6d704b3807b83ce
- https://git.kernel.org/stable/c/5c5f02e16b919c8cb6024dc3778c8d8f1fb1f26b
- https://git.kernel.org/stable/c/6cf1a126de2992b4efe1c3c4d398f8de4aed6e3f
- https://git.kernel.org/stable/c/7291af9a738d936c2d6869d030711dceb68404d0
- https://git.kernel.org/stable/c/b9bc8fbb2d416ce87f0342478dc9fcfd79f2c65f
- https://git.kernel.org/stable/c/cbb7d8a4b4beb3061b3a1847a742983a01dca381
- https://git.kernel.org/stable/c/f53ab5a2bf20fed59a2f7542d3453228b8056358
