CVE-2024-56776
📋 TL;DR
This CVE describes a NULL pointer dereference vulnerability in the Linux kernel's STI DRM driver. If exploited, it could cause a kernel panic leading to denial of service. Systems using affected Linux kernel versions with STI graphics support are vulnerable.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic leading to system crash and denial of service, potentially requiring physical access to restart the system.
Likely Case
System crash or instability when specific graphics operations are performed, resulting in temporary denial of service.
If Mitigated
No impact if the vulnerable code path isn't triggered or if the system has proper kernel hardening protections.
🎯 Exploit Status
Exploitation requires triggering the specific code path in the STI DRM driver, likely requiring local access and specific graphics operations.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing the fix commits listed in references
Vendor Advisory: https://git.kernel.org/stable/c/40725c5fabee804fecce41d4d5c5bae80c45e1c4
Restart Required: Yes
Instructions:
1. Update Linux kernel to a patched version. 2. Check if your distribution has released security updates. 3. Rebuild kernel if compiling from source. 4. Reboot system to load new kernel.
🔧 Temporary Workarounds
Disable STI graphics support
linuxRemove or disable STI graphics driver module if not needed
modprobe -r sti_drm
echo 'blacklist sti_drm' >> /etc/modprobe.d/blacklist.conf
🧯 If You Can't Patch
- Restrict local user access to systems with STI graphics hardware
- Implement kernel hardening features like KASLR and stack protection
🔍 How to Verify
Check if Vulnerable:
Check kernel version and if STI DRM module is loaded: 'uname -r' and 'lsmod | grep sti_drm'Check Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and check kernel commit history for the fix commits📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/kern.log or dmesg
- System crash/reboot logs
Network Indicators:
- None - local vulnerability
SIEM Query:
Search for kernel panic events or system crash logs related to DRM/STI modules🔗 References
- https://git.kernel.org/stable/c/40725c5fabee804fecce41d4d5c5bae80c45e1c4
- https://git.kernel.org/stable/c/831214f77037de02afc287eae93ce97f218d8c04
- https://git.kernel.org/stable/c/8ab73ac97c0fa528f66eeccd9bb53eb6eb7d20dc
- https://git.kernel.org/stable/c/e98ff67f5a68114804607de549c2350d27628fc7
- https://git.kernel.org/stable/c/f67786293193cf01ebcc6fdbcbd1587b24f52679
- https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html
