CVE-2024-56612
📋 TL;DR
A NULL pointer dereference vulnerability in the Linux kernel's unpin_user_pages() function can cause kernel crashes when handling certain memory configurations. This affects Linux systems with specific kernel versions and boot parameters, potentially leading to denial of service. The vulnerability requires local access to trigger.
💻 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 system crash and denial of service, potentially causing data loss or service disruption.
Likely Case
System crash when running specific memory-intensive operations with certain kernel configurations, resulting in temporary denial of service.
If Mitigated
No impact if the vulnerable code path isn't triggered through specific memory operations.
🎯 Exploit Status
Exploitation requires local access and specific memory operations with particular kernel configurations.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in kernel commits 69d319450d1c651f3b05cd820ff285fdd810c032 and a1268be280d8e484ab3606d7476edd0f14bb9961
Vendor Advisory: https://git.kernel.org/stable/c/69d319450d1c651f3b05cd820ff285fdd810c032
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version. 2. Reboot system. 3. Verify kernel version matches patched release.
🔧 Temporary Workarounds
Avoid vulnerable configurations
linuxDo not use 'numa=fake=2 movablecore=4G' boot parameters and avoid running gup_longterm tests.
Remove 'numa=fake=2 movablecore=4G' from kernel boot parameters in /etc/default/grub or bootloader config
🧯 If You Can't Patch
- Restrict local user access to prevent triggering the vulnerability
- Monitor system logs for kernel panic events and implement crash recovery procedures
🔍 How to Verify
Check if Vulnerable:
Check kernel version and boot parameters: 'cat /proc/cmdline' for numa=fake=2 movablecore=4G and 'uname -r' for affected kernel versions.Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated beyond the fix commits and test with gup_longterm if safe.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- NULL pointer dereference in kernel logs
- BUG: kernel NULL pointer dereference at address: 0000000000000008
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND "NULL pointer dereference" AND "unpin_user_pages"