CVE-2022-49289
📋 TL;DR
This CVE is an integer overflow vulnerability in the Linux kernel's access_ok() function that could allow attackers to bypass memory access restrictions. It affects Linux systems where user-space processes interact with kernel memory, potentially leading to privilege escalation or information disclosure. All Linux systems using vulnerable kernel versions are affected.
💻 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 root, kernel memory corruption leading to system crash, or information disclosure of sensitive kernel memory contents.
Likely Case
Local privilege escalation allowing an unprivileged user to gain elevated privileges or access restricted kernel memory regions.
If Mitigated
Limited impact if proper access controls, SELinux/AppArmor, and kernel hardening are in place, though the vulnerability still presents a risk.
🎯 Exploit Status
Exploitation requires local access and knowledge of kernel memory layout. The vulnerability allows bypassing access checks but doesn't directly provide arbitrary code execution.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing the fix commits: 222ca305c9fd39e5ed8104da25c09b2b79a516a8, 99801e2f457824955da4aadaa035913a6dede03a, a1ad747fc1a0e06d1bf26b996ee8a56b5c8d02d8, e65d28d4e9bf90a35ba79c06661a572a38391dec
Vendor Advisory: https://git.kernel.org/stable/c/222ca305c9fd39e5ed8104da25c09b2b79a516a8
Restart Required: Yes
Instructions:
1. Update to a kernel version containing the fix commits. 2. Check your distribution's security advisories for specific patched kernel versions. 3. Reboot the system after kernel update.
🔧 Temporary Workarounds
Kernel Module Restrictions
allRestrict loading of kernel modules to prevent potential exploitation vectors
echo 1 > /proc/sys/kernel/modules_disabled
sysctl -w kernel.modules_disabled=1
🧯 If You Can't Patch
- Implement strict access controls and least privilege principles for all user accounts
- Enable kernel hardening features like SELinux, AppArmor, or grsecurity to limit impact
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with patched versions from your distribution's security advisory. Examine kernel source for the specific access_ok() implementation.Check Version:
uname -rVerify Fix Applied:
Verify kernel version after update matches patched version from vendor advisory. Check that the specific git commits are present in your kernel source.📡 Detection & Monitoring
Log Indicators:
- Kernel oops messages
- Unexpected privilege escalation events in audit logs
- Failed access control violations
Network Indicators:
- Not applicable - this is a local vulnerability
SIEM Query:
source="kernel" AND ("access_ok" OR "segmentation fault" OR "general protection fault")