Bug 2506790 (CVE-2026-64219) - CVE-2026-64219 kernel: drm/amd/display: Validate payload length and link_index in dc_process_dmub_aux_transfer_async
Summary: CVE-2026-64219 kernel: drm/amd/display: Validate payload length and link_inde...
Keywords:
Status: NEW
Alias: CVE-2026-64219
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-07-24 16:03 UTC by OSIDB Bzimport
Modified: 2026-08-20 05:22 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:


Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2026:55764 0 None None None 2026-08-17 16:51:22 UTC
Red Hat Product Errata RHSA-2026:55765 0 None None None 2026-08-17 15:30:08 UTC
Red Hat Product Errata RHSA-2026:57251 0 None None None 2026-08-20 05:22:34 UTC
Red Hat Product Errata RHSA-2026:57252 0 None None None 2026-08-20 05:13:32 UTC

Description OSIDB Bzimport 2026-07-24 16:03:01 UTC
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)

Comment 1 Mauro Matteo Cascella 2026-07-28 09:43:36 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026072416-CVE-2026-64219-75c3@gregkh/T

Comment 3 errata-xmlrpc 2026-08-17 15:30:07 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:55765 https://access.redhat.com/errata/RHSA-2026:55765

Comment 4 errata-xmlrpc 2026-08-17 16:51:21 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:55764 https://access.redhat.com/errata/RHSA-2026:55764

Comment 5 errata-xmlrpc 2026-08-20 05:13:31 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:57252 https://access.redhat.com/errata/RHSA-2026:57252

Comment 6 errata-xmlrpc 2026-08-20 05:22:33 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:57251 https://access.redhat.com/errata/RHSA-2026:57251


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