CVE-2026-64219

About vulnerability

In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Validate payload length and link_index in dc_process_dmub_aux_transfer_async

[Why&How] dc_process_dmub_aux_transfer_async() copies payload->length bytes into a 16-byte stack buffer (dpaux.data[16]) guarded only by an ASSERT(), which is a no-op in release builds. If a caller ever passes length > 16 this results in a stack buffer overflow via memcpy.

Additionally, link_index is used to dereference dc->links[] without bounds checking against dc->link_count, risking an out-of-bounds access.

Replace the ASSERT with a hard runtime check that returns false when payload->length exceeds the destination buffer size, and add a bounds check for link_index before it is used.

(cherry picked from commit ba4caa9fecdf7a38f98c878ad05a8a64148b6881)

Affected product:

AlmaLinux 9.2 ESU , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , TuxCare 9.6 ESU , Ubuntu 20.04 ELS

Affected packages:

kernel @ 5.14.0 (+5 more)

Live-patch status from KernelCare for each operating system.