CVE-2024-53167
📋 TL;DR
A NULL pointer dereference vulnerability in the Linux kernel's NFS blocklayout driver can cause kernel crashes when unmounting pNFS SCSI layout-enabled NFS mounts. This affects Linux systems using pNFS with block layout driver. The vulnerability occurs when the system attempts to unregister an invalid block device during unmount operations.
💻 Affected Systems
- Linux kernel
📦 What is this software?
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to system crash and denial of service, potentially requiring physical reboot.
Likely Case
System crash during NFS unmount operations, causing temporary service disruption.
If Mitigated
No impact if patched or if pNFS block layout is not used.
🎯 Exploit Status
Exploitation requires local access or NFS client access to trigger the unmount condition.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel branches via git commits referenced in CVE
Vendor Advisory: https://git.kernel.org/stable/c/3402704a424f34bbcca7f4a4503859357f422217
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from distribution vendor. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable pNFS block layout
linuxPrevent use of pNFS block layout driver which contains the vulnerable code path.
echo "options nfs layout=none" > /etc/modprobe.d/nfs.conf
update-initramfs -u
reboot
🧯 If You Can't Patch
- Restrict NFS mount/unmount privileges to trusted users only
- Monitor for system crashes and investigate NFS unmount operations
🔍 How to Verify
Check if Vulnerable:
Check if pNFS block layout is in use: lsmod | grep blocklayoutdriver && check kernel version against patched releasesCheck Version:
uname -rVerify Fix Applied:
Verify kernel version is updated beyond patch commit dates and test NFS unmount operations📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- NULL pointer dereference errors in kernel logs
- NFS unmount failure messages
Network Indicators:
- Unexpected NFS disconnections followed by system instability
SIEM Query:
source="kernel" AND ("NULL pointer dereference" OR "panic" OR "Oops") AND "blocklayout"