CVE-2026-23341: Linux Kernel amdxdna DOS Vulnerability

CVE-2026-23341 Overview

CVE-2026-23341 is a Null Pointer Dereference vulnerability in the Linux kernel's accel/amdxdna driver. The vulnerability occurs when userspace issues an ioctl to destroy a hardware context that has already been automatically suspended, causing the driver to crash due to an attempt to access a NULL mailbox channel pointer.

Critical Impact
Local users can trigger a kernel crash by destroying a suspended hardware context, leading to denial of service conditions on systems using AMD XDNA accelerator hardware.

Affected Products

Linux kernel with accel/amdxdna driver enabled
Systems utilizing AMD XDNA accelerator hardware
Linux distributions shipping affected kernel versions

Discovery Timeline

2026-03-25 - CVE CVE-2026-23341 published to NVD
2026-03-25 - Last updated in NVD database

Technical Details for CVE-2026-23341

Vulnerability Analysis

This vulnerability exists in the AMD XDNA accelerator driver (accel/amdxdna) within the Linux kernel. The issue manifests when there is a race condition or timing issue between the automatic suspension mechanism of a hardware context and a userspace-initiated destruction request.

When a hardware context is suspended, the associated mailbox channel pointer is set to NULL as part of the suspension process. However, the aie2_destroy_context() function did not properly validate this pointer before attempting to access it. This oversight means that if a user attempts to destroy a context that has already been suspended, the driver will attempt to dereference a NULL pointer, resulting in a kernel crash.

The vulnerability is exploitable by local users who have access to the accelerator device and can issue the appropriate ioctl calls. While this requires local access and specific hardware configuration, it represents a reliable denial of service vector on affected systems.

Root Cause

The root cause of this vulnerability is a missing NULL pointer check in the aie2_destroy_context() function. The function assumed the mailbox channel pointer would always be valid when destroying a context, but this assumption is violated when the context has been automatically suspended prior to the destruction request.

The fix implements a proper validation check for the mailbox channel pointer before accessing it, ensuring that the driver gracefully handles the case where the context has already been suspended.

Attack Vector

An attacker with local access to a system with AMD XDNA accelerator hardware can exploit this vulnerability through the following sequence:

Create a hardware context using the AMDXDNA driver
Wait for or trigger the automatic suspension of the hardware context
Issue an ioctl to destroy the suspended hardware context
The driver attempts to access the NULL mailbox channel pointer
A kernel NULL pointer dereference occurs, causing a system crash

The attack requires local access to the accelerator device but does not require elevated privileges beyond the ability to interact with the AMDXDNA driver.

Detection Methods for CVE-2026-23341

Indicators of Compromise

Kernel panic or oops messages referencing the aie2_destroy_context function
System crashes occurring when AMD XDNA accelerator workloads are being terminated
Kernel logs showing NULL pointer dereference in the accel/amdxdna module

Detection Strategies

Monitor kernel logs for NULL pointer dereference errors in the AMDXDNA driver namespace
Implement crash dump analysis to identify patterns consistent with this vulnerability
Track system stability metrics on hosts with AMD XDNA accelerator hardware

Monitoring Recommendations

Enable kernel crash dump collection to capture evidence of exploitation attempts
Monitor for unusual patterns of hardware context creation and destruction
Set up alerts for kernel panic events on systems with AMD XDNA accelerators

How to Mitigate CVE-2026-23341

Immediate Actions Required

Update the Linux kernel to a patched version that includes the fix for CVE-2026-23341
If patching is not immediately possible, consider disabling the AMDXDNA driver on affected systems
Restrict access to the accelerator device to trusted users only
Monitor systems for signs of exploitation or instability

Patch Information

The vulnerability has been addressed in the Linux kernel through commits that add proper NULL pointer validation in the aie2_destroy_context() function. The fix ensures the mailbox channel pointer is checked before access, preventing the crash when destroying suspended contexts.

Patch commits are available at:

Workarounds

Restrict access to /dev/accel* devices to trusted users through proper file permissions
Consider blacklisting the amdxdna kernel module if the accelerator hardware is not required
Implement additional access controls using kernel security modules (SELinux, AppArmor)

bash

# Temporary workaround: Restrict access to AMDXDNA device
sudo chmod 600 /dev/accel*

# Alternative: Blacklist the module if not needed
echo "blacklist amdxdna" | sudo tee /etc/modprobe.d/amdxdna-blacklist.conf
sudo update-initramfs -u