CVE-2025-38427
📋 TL;DR
A memory access vulnerability in the Linux kernel's video subsystem allows invalid access to I/O memory when framebuffers are relocated behind PCI bridges. This affects Linux systems with PCI graphics devices where firmware assigns different memory offsets during boot. The vulnerability could lead to system instability or crashes.
💻 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 →⚠️ Risk & Real-World Impact
Worst Case
Kernel panic or system crash due to invalid memory access, potentially causing denial of service.
Likely Case
System instability, graphical artifacts, or application crashes when accessing framebuffer memory.
If Mitigated
Minor performance impact or no noticeable effect with proper kernel configuration.
🎯 Exploit Status
Exploitation requires specific hardware configuration and local access. Likely used for denial of service rather than privilege escalation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Patches available in stable kernel trees (commits referenced in CVE)
Vendor Advisory: https://git.kernel.org/stable/c/2f29b5c231011b94007d2c8a6d793992f2275db1
Restart Required: Yes
Instructions:
1. Update Linux kernel to patched version from distribution vendor. 2. Reboot system to load new kernel. 3. Verify kernel version matches patched release.
🔧 Temporary Workarounds
Disable affected framebuffer drivers
linuxBlacklist or disable efifb and other framebuffer drivers that use screen_info
echo 'blacklist efifb' >> /etc/modprobe.d/blacklist.conf
update-initramfs -u
🧯 If You Can't Patch
- Avoid using PCI graphics devices with firmware that relocates framebuffers
- Use text-only mode or disable graphical framebuffer initialization
🔍 How to Verify
Check if Vulnerable:
Check kernel version and compare with patched releases from distribution vendorCheck Version:
uname -rVerify Fix Applied:
Verify kernel version is updated and system boots without framebuffer-related errors📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- Invalid memory access errors in dmesg
- PCI resource allocation failures
Network Indicators:
- None - local vulnerability only
SIEM Query:
kernel: *invalid* *ioremap* OR kernel: *pci* *resource* *conflict*