CVE-2022-50262
📋 TL;DR
A NULL pointer dereference vulnerability in the Linux kernel's NTFS3 filesystem driver allows attackers to cause a kernel panic (denial of service) by mounting a specially crafted NTFS image. This affects systems using the NTFS3 driver (introduced in kernel 5.15) with vulnerable kernel versions. The vulnerability requires local access to mount malicious filesystems.
💻 Affected Systems
- Linux kernel with NTFS3 driver
📦 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to system crash and denial of service, potentially causing data loss or service disruption.
Likely Case
Local denial of service through system crash when mounting malicious NTFS images.
If Mitigated
No impact if proper access controls prevent unauthorized users from mounting filesystems.
🎯 Exploit Status
Requires creating a malicious NTFS image and mounting it. Exploitation requires local access and mount privileges.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel 5.19+ with commit 0b66046266690454dc04e6307bcff4a5605b42a1 or later
Vendor Advisory: https://git.kernel.org/stable/c/0b66046266690454dc04e6307bcff4a5605b42a1
Restart Required: Yes
Instructions:
1. Update Linux kernel to version 5.19 or later with the fix. 2. For older kernels, apply the specific patch from kernel git repository. 3. Reboot system to load patched kernel.
🔧 Temporary Workarounds
Disable NTFS3 driver
LinuxPrevent loading of the vulnerable NTFS3 driver module
echo 'blacklist ntfs3' >> /etc/modprobe.d/blacklist-ntfs3.conf
rmmod ntfs3
Restrict mount privileges
LinuxLimit which users can mount filesystems using sudoers or other access controls
# In /etc/sudoers, restrict mount command usage
# Example: username ALL=(ALL) !/bin/mount
🧯 If You Can't Patch
- Implement strict access controls to prevent unauthorized users from mounting filesystems
- Monitor for unusual mount activity and kernel panic logs
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if NTFS3 module is loaded: uname -r && lsmod | grep ntfs3Check Version:
uname -rVerify Fix Applied:
Verify kernel version is 5.19+ or check if patch is applied by examining kernel source/git history📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages referencing 'ni_find_attr' or 'NULL pointer dereference'
- Mount operations on unusual NTFS images
Network Indicators:
- Not applicable - local vulnerability
SIEM Query:
source="kernel" AND ("NULL pointer dereference" OR "ni_find_attr" OR "BUG: kernel")