CVE-2022-48932
📋 TL;DR
A buffer overflow vulnerability in the Linux kernel's mlx5 driver allows attackers to cause kernel memory corruption by creating rules with too many destinations. This affects systems using Mellanox network adapters with the mlx5 driver. The vulnerability can lead to system crashes or potential privilege escalation.
💻 Affected Systems
- Linux kernel with mlx5 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to denial of service, or potential privilege escalation if memory corruption can be controlled to execute arbitrary code.
Likely Case
System crash or kernel panic causing denial of service on affected systems.
If Mitigated
Limited impact with proper access controls preventing unprivileged users from creating network rules.
🎯 Exploit Status
Requires local access and ability to create specific network rules. No public exploits known.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel with commits 0aec12d97b2036af0946e3d582144739860ac07b and 4ad319cdfbe555b4ff67bc608736c46a6930c848
Vendor Advisory: https://git.kernel.org/stable/c/0aec12d97b2036af0946e3d582144739860ac07b
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Reboot system to load new kernel. 3. Verify kernel version after reboot.
🔧 Temporary Workarounds
Restrict network rule creation
linuxLimit ability to create network rules to trusted users only
Use Linux capabilities or SELinux/AppArmor to restrict network configuration
Disable mlx5 driver if not needed
linuxRemove or blacklist mlx5 driver if Mellanox adapters are not used
echo 'blacklist mlx5_core' > /etc/modprobe.d/blacklist-mlx5.conf
update-initramfs -u
reboot
🧯 If You Can't Patch
- Restrict access to network configuration tools and interfaces
- Implement strict access controls to prevent unauthorized users from creating network rules
🔍 How to Verify
Check if Vulnerable:
Check if system uses mlx5 driver: lsmod | grep mlx5. Check kernel version against patched versions.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits: uname -r. Check if mlx5 driver loads without issues.📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- KASAN error messages related to mlx5_cmd_dr_create_fte
- System crash dumps
Network Indicators:
- Unexpected network rule creation attempts
SIEM Query:
source="kernel" AND ("KASAN" OR "slab-out-of-bounds" OR "mlx5")