CVE-2022-27666
📋 TL;DR
CVE-2022-27666 is a heap buffer overflow vulnerability in the Linux kernel's IPsec ESP transformation code. It allows local attackers with standard user privileges to overwrite kernel heap objects, potentially leading to privilege escalation. Systems running affected Linux kernel versions with IPsec ESP enabled are vulnerable.
💻 Affected Systems
- Linux Kernel
📦 What is this software?
Fedora by Fedoraproject
Fedora by Fedoraproject
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, complete system compromise, and potential lateral movement within the network.
Likely Case
Local privilege escalation allowing attackers to gain root access on vulnerable systems.
If Mitigated
Limited impact if proper access controls restrict local user accounts and IPsec is not used.
🎯 Exploit Status
Exploitation requires local access and IPsec ESP to be active. Proof-of-concept code has been published.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel 5.16.12 and later, or backported patches for affected versions
Vendor Advisory: https://bugzilla.redhat.com/show_bug.cgi?id=2061633
Restart Required: Yes
Instructions:
1. Update Linux kernel to version 5.16.12 or later. 2. For older supported versions, apply vendor-provided patches. 3. Reboot the system after patching.
🔧 Temporary Workarounds
Disable IPsec ESP
linuxDisable IPsec ESP transformation if not required for system functionality
# Remove IPsec policies and configurations
# Check with: ip xfrm policy
# Disable with: ip xfrm policy flush
Restrict local user access
allImplement strict access controls to limit local user accounts on affected systems
🧯 If You Can't Patch
- Disable IPsec ESP functionality entirely if not required
- Implement strict user access controls and monitor for suspicious local privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check kernel version with 'uname -r' and verify if IPsec ESP is configured with 'ip xfrm policy'Check Version:
uname -rVerify Fix Applied:
Verify kernel version is 5.16.12 or later, or check with vendor-specific security update verification commands📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- OOM (Out of Memory) kernel messages
- Failed IPsec connection attempts from local users
Network Indicators:
- Unusual IPsec traffic patterns from local systems
SIEM Query:
source="kernel" AND ("panic" OR "Oops" OR "general protection fault") AND process="esp4" OR process="esp6"🔗 References
- https://bugzilla.redhat.com/show_bug.cgi?id=2061633
- https://github.com/torvalds/linux/commit/ebe48d368e97d007bfeb76fcb065d6cfc4c96645
- https://security.netapp.com/advisory/ntap-20220429-0001/
- https://www.debian.org/security/2022/dsa-5127
- https://www.debian.org/security/2022/dsa-5173
- https://bugzilla.redhat.com/show_bug.cgi?id=2061633
- https://github.com/torvalds/linux/commit/ebe48d368e97d007bfeb76fcb065d6cfc4c96645
- https://security.netapp.com/advisory/ntap-20220429-0001/
- https://www.debian.org/security/2022/dsa-5127
- https://www.debian.org/security/2022/dsa-5173
