CVE-2022-48950
📋 TL;DR
This is a use-after-free vulnerability in the Linux kernel's performance monitoring subsystem (perf). It allows attackers with local access to trigger memory corruption, potentially leading to privilege escalation or system crashes. All Linux systems using affected kernel versions 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 →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 →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 →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 root, kernel panic causing denial of service, or arbitrary code execution in kernel context.
Likely Case
Kernel panic leading to system crash/reboot, or local privilege escalation if combined with other vulnerabilities.
If Mitigated
Limited to denial of service if proper kernel hardening and privilege separation are in place.
🎯 Exploit Status
Requires local access and knowledge of kernel exploitation techniques. The use-after-free pattern is well-understood by exploit developers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patched in kernel commits: 517e6a301f34613bff24a8e35b5455884f2d83d8, 78e1317a174edbfd1182599bf76c092a2877672c, 8bffa95ac19ff27c8261904f89d36c7fcf215d59
Vendor Advisory: https://git.kernel.org/stable/c/517e6a301f34613bff24a8e35b5455884f2d83d8
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Check your distribution's security advisories for specific patched versions. 3. Reboot system after kernel update.
🔧 Temporary Workarounds
Disable perf subsystem
linuxPrevents access to perf events which could trigger the vulnerability
echo 0 > /proc/sys/kernel/perf_event_paranoid
chmod 000 /usr/bin/perf
Restrict perf access
linuxLimit perf usage to privileged users only
echo 2 > /proc/sys/kernel/perf_event_paranoid
🧯 If You Can't Patch
- Implement strict user privilege separation to limit who can execute perf commands
- Monitor for unusual perf usage patterns and kernel panic events
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with distribution's security advisory. Run: uname -r and check if version is before patched releases.Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated to patched version. Check if /proc/sys/kernel/perf_event_paranoid is set appropriately.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- OOM killer activity related to perf
- Unusual perf command execution by non-privileged users
Network Indicators:
- None - local exploit only
SIEM Query:
Search for: 'kernel panic' OR 'perf' AND 'segfault' OR 'use-after-free' in system logs