CVE-2022-50167
📋 TL;DR
This CVE describes a 32-bit integer overflow vulnerability in the Linux kernel's BPF subsystem when accessing large ARRAY maps. Attackers could exploit this to cause kernel crashes or potentially execute arbitrary code with kernel privileges. All Linux systems using affected kernel versions with BPF enabled 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to denial of service, or potential privilege escalation to kernel-level code execution allowing complete system compromise.
Likely Case
Kernel crash or denial of service through system instability, requiring reboot to restore functionality.
If Mitigated
No impact if BPF is disabled or systems are patched; limited impact if proper kernel hardening and isolation are implemented.
🎯 Exploit Status
Exploitation requires ability to load and execute BPF programs, which typically requires CAP_BPF or CAP_SYS_ADMIN capabilities. No public exploits have been reported.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits 063e092534d4c6785228e5b1eb6e9329f66ccbe4, 3c7256b880b3a5aa1895fd169a34aa4224a11862, or 87ac0d600943994444e24382a87aa19acc4cd3d4
Vendor Advisory: https://git.kernel.org/stable/c/063e092534d4c6785228e5b1eb6e9329f66ccbe4
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 BPF functionality
linuxPrevent loading of BPF programs by disabling BPF syscalls
sysctl -w kernel.unprivileged_bpf_disabled=1
echo 1 > /proc/sys/kernel/unprivileged_bpf_disabled
Restrict BPF capabilities
linuxUse Linux Security Modules to restrict BPF usage
setcap -r /usr/bin/bpftool
configure SELinux/AppArmor to deny bpf syscalls
🧯 If You Can't Patch
- Implement strict capability management to prevent unprivileged users from loading BPF programs
- Deploy kernel hardening solutions like grsecurity or PaX to mitigate exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with patched versions from your distribution; verify if BPF is enabled via /proc/sys/kernel/unprivileged_bpf_disabledCheck Version:
uname -rVerify Fix Applied:
Verify kernel version contains the fix commits; test BPF functionality with controlled programs📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages in dmesg or /var/log/kern.log
- System crash/reboot events without clear cause
- Failed BPF program loads with error codes
Network Indicators:
- Unusual system instability or crashes following BPF-related activity
SIEM Query:
source="kernel" AND ("Oops" OR "general protection fault" OR "kernel panic") AND ("bpf" OR "BPF")