CVE-2025-39809
📋 TL;DR
A stack buffer overflow vulnerability in the Linux kernel's Intel QuickI2C driver allows local attackers to write beyond allocated memory bounds. This affects systems with Intel THC-HID hardware using ACPI DSD methods. The vulnerability can lead to kernel crashes or potential privilege escalation.
💻 Affected Systems
- Linux kernel with Intel QuickI2C driver (intel_quicki2c)
📦 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
Local privilege escalation to kernel mode, complete system compromise, or persistent denial of service.
Likely Case
Kernel panic leading to system crash and denial of service, requiring physical or remote console access to recover.
If Mitigated
System crash requiring reboot, but no privilege escalation if kernel hardening features like KASAN are enabled.
🎯 Exploit Status
Requires local access and specific hardware configuration. The stack trace shows KASAN detection, making exploitation more difficult on hardened systems.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel with commits 1db9df89a213318a48d958385dc1b17b379dc32b and 4adce86d4b13d15dec7810967839b931b1598700 applied
Vendor Advisory: https://git.kernel.org/stable/c/1db9df89a213318a48d958385dc1b17b379dc32b
Restart Required: Yes
Instructions:
1. Update Linux kernel to version containing the fix commits. 2. Reboot system to load new kernel. 3. Verify driver is no longer vulnerable.
🔧 Temporary Workarounds
Disable Intel QuickI2C driver
linuxBlacklist or prevent loading of the vulnerable intel_quicki2c kernel module
echo 'blacklist intel_quicki2c' >> /etc/modprobe.d/blacklist-intel-quicki2c.conf
update-initramfs -u
reboot
Disable ACPI DSD methods for affected hardware
linuxPrevent ACPI from exposing the vulnerable DSD methods
Add 'acpi=off' or specific ACPI blacklisting to kernel boot parameters in /etc/default/grub
🧯 If You Can't Patch
- Restrict local user access to systems with vulnerable hardware
- Enable kernel hardening features like KASAN, stack canaries, and KPTI
🔍 How to Verify
Check if Vulnerable:
Check if intel_quicki2c module is loaded: lsmod | grep intel_quicki2c. Check kernel version against patched versions.Check Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commits. Check dmesg for absence of stack-out-of-bounds errors related to quicki2c_acpi_get_dsd_property.📡 Detection & Monitoring
Log Indicators:
- Kernel logs showing 'KASAN: stack-out-of-bounds' errors
- Kernel panic messages mentioning quicki2c_acpi_get_dsd_property
- System crashes with intel_quicki2c module in stack trace
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="kernel" AND ("stack-out-of-bounds" OR "quicki2c" OR "intel_quicki2c")