CVE-2025-38449
📋 TL;DR
A use-after-free vulnerability in the Linux kernel's DRM/GEM subsystem allows a local attacker to cause a kernel crash (segmentation fault) by manipulating graphics buffer handles while they're still in use by framebuffers. This affects systems with DRM drivers that use shadow planes for vmap-ing dma-bufs during page flips. The vulnerability can lead to denial of service.
💻 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 and denial of service, potentially requiring physical access or reboot to restore functionality.
Likely Case
Kernel crash or instability when performing graphics operations, leading to application crashes or system hangs.
If Mitigated
No impact if patched; unpatched systems remain vulnerable to local denial of service attacks.
🎯 Exploit Status
Exploitation requires local access and ability to perform graphics operations that trigger the use-after-free condition.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions with fixes from the provided git commits
Vendor Advisory: https://git.kernel.org/stable/c/08480e285c6a82ce689008d643e4a51db0aaef8b
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing fixes from provided git commits
2. Reboot system to load new kernel
3. Verify kernel version after reboot
🔧 Temporary Workarounds
Disable affected graphics drivers
linuxTemporarily disable DRM drivers that use shadow planes if not required
modprobe -r [affected_drm_driver]
🧯 If You Can't Patch
- Restrict local user access to systems with graphics operations
- Monitor system logs for segmentation fault warnings related to dma_buf_vmap
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with affected versions. Look for kernel logs containing 'dma_buf_vmap' segmentation faults.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fixes from provided git commits. Test graphics operations that previously caused crashes.📡 Detection & Monitoring
Log Indicators:
- Kernel logs showing 'dma_buf_vmap' segmentation faults
- Warnings about DMA buffer operations failing
Network Indicators:
- None - local vulnerability only
SIEM Query:
source="kernel" AND ("dma_buf_vmap" OR "segmentation fault" OR "WARNING: CPU")