CVE-2022-49629
📋 TL;DR
This CVE describes a race condition vulnerability in the Linux kernel's nexthop subsystem where concurrent access to the nexthop_compat_mode variable without proper synchronization could lead to inconsistent state. This affects Linux systems using nexthop functionality, potentially causing network instability or crashes. The vulnerability requires local access to exploit.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic or system crash leading to denial of service, potentially disrupting network connectivity on affected systems.
Likely Case
Network instability or packet loss due to inconsistent nexthop state, requiring system restart to recover.
If Mitigated
Minor performance impact from race condition protection with no security compromise.
🎯 Exploit Status
Race conditions are difficult to reliably exploit and typically require local access. No known public exploits exist.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel trees (commits: 0d17723afea3ae8c9f245c9bbd2ba5945b77e812, a51040d4b120f3520df64fb0b9c63b31d69bea9b, ae3054f6fbccc90f14ecd6cf9b2c09a2401c64fd, bdf00bf24bef9be1ca641a6390fd5487873e0d2e)
Vendor Advisory: https://git.kernel.org/stable/c/0d17723afea3ae8c9f245c9bbd2ba5945b77e812
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 matches patched release.
🔧 Temporary Workarounds
Restrict local access
linuxLimit local user access to systems to reduce attack surface
Disable unnecessary nexthop features
linuxIf nexthop functionality is not required, consider disabling related kernel modules
modprobe -r <nexthop_module>
🧯 If You Can't Patch
- Implement strict access controls to limit local user privileges
- Monitor system logs for kernel panics or network instability indicators
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with patched versions from distribution vendor. Examine if nexthop functionality is enabled.Check Version:
uname -rVerify Fix Applied:
Verify kernel version matches patched release from your distribution. Check that system is stable during network operations.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- Network subsystem errors in dmesg
- System crash reports
Network Indicators:
- Unexplained network connectivity loss
- Increased packet loss
SIEM Query:
source="kernel" AND ("panic" OR "Oops" OR "nexthop")