CVE-2024-46687
📋 TL;DR
A use-after-free vulnerability in the Linux kernel's Btrfs filesystem allows attackers to potentially crash the system or execute arbitrary code with kernel privileges. This affects Linux systems using Btrfs filesystem when encountering specific I/O errors during read operations. 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 →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 leading to system crash or potential privilege escalation allowing arbitrary code execution with kernel privileges.
Likely Case
System crash or kernel panic causing denial of service, potentially requiring physical access to restart the system.
If Mitigated
Limited to denial of service if exploit fails or system has additional hardening measures.
🎯 Exploit Status
Requires triggering specific I/O error conditions during Btrfs read operations. Exploitation requires local access and knowledge of filesystem operations.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Fixed in Linux kernel stable releases containing commits 10d9d8c3512f16cad47b2ff81ec6fc4b27d8ee10, 4a3b9e1a8e6cd1a8d427a905e159de58d38941cc, or 51722b99f41f5e722ffa10b8f61e802a0e70b331
Vendor Advisory: https://git.kernel.org/stable/c/10d9d8c3512f16cad47b2ff81ec6fc4b27d8ee10
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix. 2. Check with your distribution for specific kernel package updates. 3. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable Btrfs filesystem
linuxSwitch to alternative filesystem like ext4 or XFS for affected systems
# Backup data first
# Format partition with alternative filesystem
# Update /etc/fstab to use new filesystem
Restrict filesystem access
linuxLimit user access to Btrfs filesystems to reduce attack surface
# Use filesystem permissions
# Implement mandatory access controls (SELinux/AppArmor)
# Restrict user privileges
🧯 If You Can't Patch
- Implement strict access controls to limit who can access Btrfs filesystems
- Monitor system logs for kernel panics or Btrfs-related errors and implement automated alerting
🔍 How to Verify
Check if Vulnerable:
Check kernel version and verify Btrfs is in use: uname -r && cat /proc/filesystems | grep btrfsCheck Version:
uname -rVerify Fix Applied:
Verify kernel version is updated to include fix commits and test Btrfs operations📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- Btrfs error messages in dmesg or /var/log/kern.log
- KASAN use-after-free reports
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("KASAN" OR "use-after-free" OR "Btrfs" AND "error")