CVE-2023-53389: drm/mediatek: dp: Only trigger DRM HPD events if bridge is attached

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-09-18 · updated 2026-06-17
Weakness: CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: drm/mediatek: dp: Only trigger DRM HPD events if bridge is attached The MediaTek DisplayPort interface bridge driver starts its interrupts as soon as its probed. However when the interrupts trigger the bridge might not have been attached to a DRM device. As drm_helper_hpd_irq_event() does not check whether the passed in drm_device is valid or not, a NULL pointer passed in results in a kernel NULL pointer dereference in it. Check whether the bridge is attached and only trigger an HPD event if it is.

Affected products

Linux kernel: from 6.1 before 6.1.28; from 6.2 before 6.2.15; from 6.3 before 6.3.2 — fixed in 6.1.28, 6.2.15, 6.3.2

How to fix

Upgrade to a fixed version: Linux kernel 6.1.28, 6.2.15, 6.3.2. Check the vendor advisory for mitigations.

References

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