CVE-2022-48718
📋 TL;DR
This CVE describes a NULL pointer dereference vulnerability in the Linux kernel's mxsfb DRM driver. When exploited, it can cause kernel crashes or potentially lead to privilege escalation. Systems running affected Linux kernel versions with the mxsfb driver loaded are vulnerable.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to system crash, or potential privilege escalation to kernel mode execution.
Likely Case
System crash or denial of service when the vulnerable code path is triggered.
If Mitigated
Limited impact due to the specific driver requirement and local access needed for exploitation.
🎯 Exploit Status
Exploitation requires local access and triggering the specific vulnerable code path in the mxsfb driver.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel trees (commits: 622c9a3a7868e1eeca39c55305ca3ebec4742b64, 6f9267e01cca749137349d8ffb0d0ebbadf567f4, 86a337bb803040e4401b87c974a7fb92efe3d0e1)
Vendor Advisory: https://git.kernel.org/stable/c/622c9a3a7868e1eeca39c55305ca3ebec4742b64
Restart Required: Yes
Instructions:
1. Update Linux kernel to a patched version from your distribution's repositories. 2. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable mxsfb driver
linuxPrevent loading of the vulnerable mxsfb DRM driver
echo 'blacklist mxsfb' >> /etc/modprobe.d/blacklist-mxsfb.conf
update-initramfs -u
🧯 If You Can't Patch
- Restrict local access to systems to prevent potential exploitation
- Implement kernel module signing to prevent unauthorized driver loading
🔍 How to Verify
Check if Vulnerable:
Check if mxsfb driver is loaded: lsmod | grep mxsfbCheck Version:
uname -rVerify Fix Applied:
Check kernel version against patched versions from your distribution's security advisories📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/kern.log or dmesg
- NULL pointer dereference errors in kernel logs
Network Indicators:
- No network indicators - local vulnerability
SIEM Query:
source="kernel" AND ("NULL pointer dereference" OR "kernel panic" OR "mxsfb")🔗 References
- https://git.kernel.org/stable/c/622c9a3a7868e1eeca39c55305ca3ebec4742b64
- https://git.kernel.org/stable/c/6f9267e01cca749137349d8ffb0d0ebbadf567f4
- https://git.kernel.org/stable/c/86a337bb803040e4401b87c974a7fb92efe3d0e1
- https://git.kernel.org/stable/c/622c9a3a7868e1eeca39c55305ca3ebec4742b64
- https://git.kernel.org/stable/c/6f9267e01cca749137349d8ffb0d0ebbadf567f4
- https://git.kernel.org/stable/c/86a337bb803040e4401b87c974a7fb92efe3d0e1
