CVE-2022-49426
📋 TL;DR
This is a use-after-free vulnerability in the Linux kernel's ARM SMMU v3 SVA (Shared Virtual Addressing) subsystem. It allows attackers with local access to potentially escalate privileges or cause denial of service by exploiting improper memory management. Systems running affected Linux kernel versions with ARM SMMU v3 hardware 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 →⚠️ Risk & Real-World Impact
Worst Case
Local privilege escalation to kernel-level access, potentially leading to full system compromise, data theft, or persistent backdoor installation.
Likely Case
Kernel panic or system crash causing denial of service, potentially requiring physical reboot.
If Mitigated
Limited impact if proper access controls prevent local user access or if vulnerable components are not in use.
🎯 Exploit Status
Requires local access and knowledge of kernel memory management. No public exploits known as of knowledge cutoff.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel branches via provided git commits
Vendor Advisory: https://git.kernel.org/stable/c/9aa215450888cf29af0c479e14a712dc6b0c506c
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from your distribution's repositories. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Disable SVA feature
ARM systems with SMMU v3Disable Shared Virtual Addressing feature in kernel boot parameters if not required
Add 'iommu.passthrough=1' or 'iommu=off' to kernel boot parameters (GRUB_CMDLINE_LINUX in /etc/default/grub)
🧯 If You Can't Patch
- Restrict local user access to essential personnel only
- Implement strict privilege separation and use SELinux/AppArmor to limit kernel access
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if ARM SMMU v3 is present: 'uname -r' and 'dmesg | grep -i smmu'Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and check dmesg for successful SMMU initialization without errors📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- SMMU-related errors in dmesg
- Unexpected process crashes with memory access violations
Network Indicators:
- None - local vulnerability only
SIEM Query:
Search for: 'kernel panic' OR 'use-after-free' OR 'smmu' in system logs