CVE-2023-53784 drm: bridge: dw_hdmi: fix connector access for scdc
A null pointer dereference in the Linux kernel's DW-HDMI driver can cause a system crash when accessing SCDC debug information.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-53784?
CVE-2023-53784 is a vulnerability in Linux, published on 9 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
drm: bridge: dw_hdmi: fix connector access for scdc
Commit 5d844091f237 ("drm/scdc-helper: Pimp SCDC debugs") changed the scdc interface to pick up an i2c adapter from a connector instead. However, in the case of dw-hdmi, the wrong connector was being used to pass i2c adapter information, since dw-hdmi's embedded connector structure is only populated when the bridge attachment callback explicitly asks for it.
drm-meson is handling connector creation, so this won't happen, leading to a NULL pointer dereference.
Fix it by having scdc functions access dw-hdmi's current connector pointer instead, which is assigned during the bridge enablement stage.
[narmstrong: moved Fixes tag before first S-o-b and added Reported-by tag]
Which versions are affected by CVE-2023-53784?
How do I fix CVE-2023-53784?
Apply the vendor's patch.
Is CVE-2023-53784 being exploited?
There is no known exploitation of CVE-2023-53784 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-53784, DEBIAN-CVE-2023-53784, GHSA-phmc-8r45-84x7, UBUNTU-CVE-2023-53784.