CVE-2025-71308 Overview
CVE-2025-71308 is a NULL pointer dereference vulnerability in the Linux kernel's accel/amdxdna driver, which supports AMD XDNA AI Engine accelerators. The flaw resides in the context cleanup path invoked during error handling in aie2_create_context(). When mailbox channel creation fails, the channel pointer remains NULL, but aie_destroy_context() dereferences it without a check. The defect can trigger a kernel crash during error handling on systems using AMD XDNA accelerator hardware. The issue has been resolved upstream by replacing the unsafe cleanup call with a function that requests firmware to remove the previously created context.
Critical Impact
Local triggering of the failure path in aie2_create_context() can dereference a NULL mailbox channel pointer and crash the kernel, producing a denial-of-service condition.
Affected Products
- Linux kernel versions containing the accel/amdxdna driver prior to the fix commits
- Systems with AMD XDNA AI Engine accelerator hardware enabled
- Distributions shipping affected stable kernel branches
Discovery Timeline
- 2026-05-27 - CVE-2025-71308 published to NVD
- 2026-05-27 - Last updated in NVD database
Technical Details for CVE-2025-71308
Vulnerability Analysis
The vulnerability sits in the AMD XDNA accelerator driver (accel/amdxdna), which manages hardware contexts on AI Engine devices. During context creation, aie2_create_context() allocates resources and establishes a mailbox channel used for firmware communication. If any step after the channel pointer is initialized to NULL fails before the channel is successfully created, the error-handling path calls aie_destroy_context() to roll back the partially constructed context.
The cleanup routine, however, assumes the mailbox channel pointer is valid and dereferences it without performing a NULL check. When channel creation fails, this assumption is violated. The resulting NULL pointer dereference [CWE-476] triggers a kernel oops and halts execution on the affected CPU, producing a denial-of-service condition for any process exercising the context-creation path.
Because the trigger lies in driver error handling rather than a security boundary, exploitation requires the ability to invoke the driver's ioctl path and induce mailbox channel creation failure, typically requiring local access to the accelerator device node.
Root Cause
The root cause is missing input validation in aie_destroy_context(). The function unconditionally accesses the context's mailbox channel pointer instead of verifying it is non-NULL before use. The original control flow allowed this destructor to be reached from error-handling branches in aie2_create_context() where the pointer was guaranteed to be uninitialized.
Attack Vector
An attacker with the ability to open the AMD XDNA accelerator character device and issue context-creation requests can attempt to force mailbox channel creation to fail, driving execution into the vulnerable cleanup path. Successful triggering crashes the kernel. The fix replaces aie_destroy_context() in the error path with a firmware request that removes the previously created context without dereferencing uninitialized state. See the kernel commits 2611c9616cb5 and 97f27573837e for the upstream patch.
Detection Methods for CVE-2025-71308
Indicators of Compromise
- Kernel oops or panic messages referencing aie_destroy_context or aie2_create_context in dmesg and /var/log/kern.log.
- NULL pointer dereference stack traces originating in the amdxdna driver module.
- Repeated process termination or service restarts after invoking AMD XDNA accelerator workloads.
Detection Strategies
- Inventory hosts where the amdxdna kernel module is loaded using lsmod | grep amdxdna and compare running kernel versions against the patched commits.
- Audit access to the AMD XDNA accelerator device node and identify non-administrative processes interacting with it.
- Correlate kernel crash telemetry with workloads using AMD AI Engine APIs to identify reproducible failure conditions.
Monitoring Recommendations
- Forward kernel ring buffer events and crash dumps to a centralized log platform for alerting on amdxdna faults.
- Monitor system uptime and unexpected reboots on AMD XDNA-enabled systems.
- Track package and kernel versions across the fleet to confirm patch deployment status.
How to Mitigate CVE-2025-71308
Immediate Actions Required
- Update to a Linux kernel release that includes commits 2611c9616cb5 and 97f27573837e from the stable tree.
- Restrict access to the AMD XDNA accelerator device node to trusted users until the patch is deployed.
- Rebuild and redeploy custom kernels that include the accel/amdxdna driver after applying the upstream fix.
Patch Information
The fix is available in the Linux stable tree. The patches replace the unsafe aie_destroy_context() call in the aie2_create_context() error path with a firmware-mediated removal of the previously created context. Apply the changes referenced in kernel commit 2611c9616cb5 and kernel commit 97f27573837e, then rebuild and reboot affected systems.
Workarounds
- Unload the amdxdna module with modprobe -r amdxdna on systems that do not require AMD XDNA accelerator functionality.
- Blacklist the amdxdna module in /etc/modprobe.d/ to prevent automatic loading at boot until patched kernels are deployed.
- Limit device permissions on /dev/accel/* nodes so only privileged service accounts can open them.
# Prevent the amdxdna driver from loading until patched kernels are deployed
echo "blacklist amdxdna" | sudo tee /etc/modprobe.d/blacklist-amdxdna.conf
sudo modprobe -r amdxdna 2>/dev/null || true
sudo update-initramfs -u
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
