CVE-2022-50269
📋 TL;DR
This CVE describes a memory leak vulnerability in the Linux kernel's vkms (Virtual Kernel Mode Setting) driver. When the vkms module installation fails during initialization, allocated memory isn't properly freed, leading to resource exhaustion over time. This affects Linux systems using the vkms driver, primarily those with DRM/KMS graphics support.
💻 Affected Systems
- Linux kernel with vkms 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
Sustained exploitation could lead to kernel memory exhaustion, causing system instability, crashes, or denial of service through resource depletion.
Likely Case
Repeated failed vkms module loads gradually consume kernel memory, potentially degrading system performance or causing kernel panics over extended periods.
If Mitigated
With proper monitoring and limited vkms usage, impact is minimal as the leak only occurs during module installation failures.
🎯 Exploit Status
Exploitation requires local access and ability to load kernel modules. The vulnerability only triggers when vkms_create() fails during module initialization.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel with commits: 07ab77154d6fd2d67e465ab5ce30083709950f02, 0d0b368b9d104b437e1f4850ae94bdb9a3601e89, bad13de764888b765ceaa4668893b52bd16653cc, bebd60ec3bf21062f103e32e6203c6daabdbd51b
Vendor Advisory: https://git.kernel.org/stable/c/07ab77154d6fd2d67e465ab5ce30083709950f02
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution vendor. 2. Reboot system to load new kernel. 3. Verify vkms module loads correctly if needed.
🔧 Temporary Workarounds
Disable vkms module
allPrevent vkms module from loading to avoid vulnerability trigger
echo 'blacklist vkms' >> /etc/modprobe.d/blacklist-vkms.conf
rmmod vkms 2>/dev/null || true
Restrict module loading
allLimit kernel module loading to authorized users only
sysctl -w kernel.modules_disabled=1
echo 'kernel.modules_disabled=1' >> /etc/sysctl.d/99-module-security.conf
🧯 If You Can't Patch
- Monitor kernel memory usage for unusual patterns
- Restrict local user access to prevent malicious module loading attempts
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if vkms module is loaded: lsmod | grep vkms && uname -rCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits or is newer than vulnerable versions📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages related to vkms
- System logs showing repeated vkms module load failures
- Kernel memory allocation failures in dmesg
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="kernel" AND ("vkms" OR "memory leak" OR "kmalloc")