CVE-2026-43191
Published: May 6, 2026· Updated: May 11, 2026
Official Description
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Adjust PHY FSM transition to TX_EN-to-PLL_ON for TMDS on DCN35
[Why]
A backport of the change made for DCN401 that addresses an issue where
we turn off the PHY PLL when disabling TMDS output, which causes the
OTG to remain stuck.
The OTG being stuck can lead to a hang in the DCHVM's ability to ACK
invalidations when it thinks the HUBP is still on but it's not receiving
global sync.
The transition to PLL_ON needs to be atomic as there's no guarantee
that the thread isn't pre-empted or is able to complete before the
IOMMU watchdog times out.
[How]
Backport the implementation from dcn401 back to dcn35.
There's a functional difference in when the eDP output is disabled in
dcn401 code so we don't want to utilize it directly.
Technical Analysis
CVE-2026-43191 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 5.5.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (2)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-43191 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts