CVE-2023-54299

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

usb: typec: bus: verify partner exists in typec_altmode_attention

Some usb hubs will negotiate DisplayPort Alt mode with the device

but will then negotiate a data role swap after entering the alt

mode. The data role swap causes the device to unregister all alt

modes, however the usb hub will still send Attention messages

even after failing to reregister the Alt Mode. type_altmode_attention

currently does not verify whether or not a device's altmode partner

exists, which results in a NULL pointer error when dereferencing

the typec_altmode and typec_altmode_ops belonging to the altmode

partner.

Verify the presence of a device's altmode partner before sending

the Attention message to the Alt Mode driver.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References