CVE-2026-43337 drm/amd/display: Fix NULL pointer dereference in dcn401_init_hw()
A NULL pointer dereference in the Linux kernel's AMD display driver can cause a system crash during hardware initialization.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-43337?
CVE-2026-43337 is a medium-severity vulnerability in Linux kernel, published on 8 May 2026. 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/amd/display: Fix NULL pointer dereference in dcn401_init_hw()
dcn401_init_hw() assumes that update_bw_bounding_box() is valid when entering the update path. However, the existing condition:
((!fams2_enable && update_bw_bounding_box) || freq_changed)
does not guarantee this, as the freq_changed branch can evaluate to true independently of the callback pointer.
This can result in calling update_bw_bounding_box() when it is NULL.
Fix this by separating the update condition from the pointer checks and ensuring the callback, dc->clk_mgr, and bw_params are validated before use.
Fixes the below: ../dc/hwss/dcn401/dcn401_hwseq.c:367 dcn401_init_hw() error: we previously assumed 'dc->res_pool->funcs->update_bw_bounding_box' could be null (see line 362)
(cherry picked from commit 86117c5ab42f21562fedb0a64bffea3ee5fcd477)
Weakness: CWE-476
Which versions are affected by CVE-2026-43337?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-43337?
Apply the vendor's patch.
Is CVE-2026-43337 being exploited?
There is no known exploitation of CVE-2026-43337 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-43337, DEBIAN-CVE-2026-43337, GHSA-5cr7-8523-mgr2, ROOT-OS-DEBIAN-13-CVE-2026-43337, UBUNTU-CVE-2026-43337.