CVE-2025-39959
📋 TL;DR
This CVE describes a null pointer dereference vulnerability in the AMD ACP I2S driver of the Linux kernel. The vulnerability occurs when the driver incorrectly retrieves chip information, potentially causing kernel crashes or denial of service. Systems running affected Linux kernel versions with AMD ACP audio hardware are at risk.
💻 Affected Systems
- Linux kernel with AMD ACP audio driver
📦 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, requiring physical or remote reboot to restore functionality.
Likely Case
Local denial of service through kernel crash when specific audio operations are performed on affected hardware.
If Mitigated
Minor system instability or audio functionality issues if exploitation attempts are partially successful.
🎯 Exploit Status
Exploitation requires local access and knowledge of specific audio operations to trigger the null pointer dereference.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Kernel versions containing commit 65c5cfbd6d938f77a0df3c34855a4f7d8a61fd10 or later
Vendor Advisory: https://git.kernel.org/stable/c/65c5cfbd6d938f77a0df3c34855a4f7d8a61fd10
Restart Required: No
Instructions:
1. Update Linux kernel to version containing the fix commit. 2. For distributions: Use package manager to update kernel package. 3. Rebuild kernel if using custom kernel. 4. No reboot required for kernel module reload, but recommended for stability.
🔧 Temporary Workarounds
Disable AMD ACP audio driver
allPrevent loading of the vulnerable kernel module
echo 'blacklist snd-soc-acp-i2s' >> /etc/modprobe.d/blacklist.conf
rmmod snd_soc_acp_i2s
🧯 If You Can't Patch
- Restrict local user access to systems with AMD ACP hardware
- Monitor for kernel panic/crash events and investigate audio-related processes
🔍 How to Verify
Check if Vulnerable:
Check if AMD ACP I2S driver is loaded: lsmod | grep snd_soc_acp_i2s && check kernel version against affected rangeCheck Version:
uname -rVerify Fix Applied:
Verify kernel version includes fix commit: grep -q '65c5cfbd6d938f77a0df3c34855a4f7d8a61fd10' /proc/version_signature or check kernel changelog📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages in /var/log/kern.log or dmesg
- NULL pointer dereference errors in kernel logs
- Audio subsystem crash logs
Network Indicators:
- None - this is a local vulnerability
SIEM Query:
source="kernel" AND ("NULL pointer dereference" OR "kernel panic" OR "ACP I2S")