CVE-2024-38629
📋 TL;DR
This CVE describes a use-after-free vulnerability in the Linux kernel's dmaengine idxd driver. The vulnerability occurs when file_ida is destroyed prematurely, potentially allowing kernel memory corruption. This affects systems running vulnerable Linux kernel versions with the idxd driver enabled.
💻 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 enabling local privilege escalation if combined with other vulnerabilities.
Likely Case
System crash or kernel panic causing denial of service when specific operations are performed on idxd devices.
If Mitigated
No impact if idxd driver is not loaded or if proper access controls prevent unauthorized users from accessing idxd device files.
🎯 Exploit Status
Exploitation requires local access and ability to interact with idxd device files. The vulnerability is triggered during specific driver cleanup operations.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commits 15edb906211bf53e7b5574f7326ab734d6bff4f9, 76e43fa6a456787bad31b8d0daeabda27351a480, or 9eb15f24a0b9b017b39cde8b8c07243676b63687
Vendor Advisory: https://git.kernel.org/stable/c/15edb906211bf53e7b5574f7326ab734d6bff4f9
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 packages. 3. Reboot the system after kernel update.
🔧 Temporary Workarounds
Disable idxd driver
linuxPrevent loading of the vulnerable idxd driver module
echo 'blacklist idxd' >> /etc/modprobe.d/blacklist.conf
rmmod idxd
🧯 If You Can't Patch
- Restrict access to idxd device files to trusted users only
- Monitor system logs for kernel panic messages related to idxd operations
🔍 How to Verify
Check if Vulnerable:
Check if idxd driver is loaded: 'lsmod | grep idxd'. If loaded, check kernel version against patched versions.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits: 'uname -r' and check with distribution vendor for patch status.📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/kern.log or dmesg output
- OOM or memory corruption errors related to idxd
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="kernel" AND ("panic" OR "Oops") AND "idxd"🔗 References
- https://git.kernel.org/stable/c/15edb906211bf53e7b5574f7326ab734d6bff4f9
- https://git.kernel.org/stable/c/76e43fa6a456787bad31b8d0daeabda27351a480
- https://git.kernel.org/stable/c/9eb15f24a0b9b017b39cde8b8c07243676b63687
- https://git.kernel.org/stable/c/15edb906211bf53e7b5574f7326ab734d6bff4f9
- https://git.kernel.org/stable/c/76e43fa6a456787bad31b8d0daeabda27351a480
- https://git.kernel.org/stable/c/9eb15f24a0b9b017b39cde8b8c07243676b63687
