CVE-2022-48811
📋 TL;DR
A NULL pointer dereference vulnerability in the Linux kernel's ibmvnic driver can cause kernel crashes when network interface operations fail. This affects Linux systems using IBM PowerVM virtual network interfaces. The vulnerability occurs during error handling in the __ibmvnic_open() function when releasing resources prematurely.
💻 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 →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 →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 disrupting critical services on affected systems.
Likely Case
System crash or instability when network interface operations fail, particularly during repeated interface add/remove operations.
If Mitigated
Minimal impact if systems are patched or not using ibmvnic driver; isolated to specific IBM PowerVM environments.
🎯 Exploit Status
Exploitation requires local access and ability to trigger network interface operations that fail. The crash occurs during error handling, not through direct malicious input.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel with commit 61772b0908c640d0309c40f7d41d062ca4e979fa or later
Vendor Advisory: https://git.kernel.org/stable/c/61772b0908c640d0309c40f7d41d062ca4e979fa
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commit. 2. For distributions: Use package manager (yum update kernel, apt-get upgrade linux-image, etc.). 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Avoid ibmvnic interface operations
linuxPrevent triggering the vulnerability by avoiding repeated add/remove operations on ibmvnic interfaces
# Avoid using drmgr command repeatedly on ibmvnic interfaces
# Monitor for interface management operations that might trigger the issue
🧯 If You Can't Patch
- Avoid using ibmvnic interfaces if possible
- Implement monitoring for kernel crashes and have recovery procedures ready
🔍 How to Verify
Check if Vulnerable:
Check if system uses ibmvnic driver: lsmod | grep ibmvnic. If present and kernel version is before the fix commit, system is vulnerable.Check Version:
uname -rVerify Fix Applied:
Check kernel version contains the fix commit: grep -q '61772b0908c640d0309c40f7d41d062ca4e979fa' /proc/version_signature || uname -r (compare with distribution's patched version)📡 Detection & Monitoring
Log Indicators:
- Kernel NULL pointer dereference messages
- ibmvnic driver crash logs
- System crash/panic logs mentioning ibmvnic
Network Indicators:
- Sudden loss of network connectivity on ibmvnic interfaces
SIEM Query:
source="kernel" AND ("NULL pointer dereference" OR "ibmvnic" OR "Kernel access of bad area")🔗 References
- https://git.kernel.org/stable/c/61772b0908c640d0309c40f7d41d062ca4e979fa
- https://git.kernel.org/stable/c/960dfaf3b578dd23af012590e809ae2d58ba1827
- https://git.kernel.org/stable/c/e08cb9056fb2564d1f6bad789bdf79ab09bf2f81
- https://git.kernel.org/stable/c/61772b0908c640d0309c40f7d41d062ca4e979fa
- https://git.kernel.org/stable/c/960dfaf3b578dd23af012590e809ae2d58ba1827
- https://git.kernel.org/stable/c/e08cb9056fb2564d1f6bad789bdf79ab09bf2f81
