CVE-2026-72483

Technical Description

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

usb: host: max3421: Fix shift-out-of-bounds in max3421_hub_control()

The `max3421_hub_control()` function handles USB hub class requests

to the virtual root hub. In the `default` branches of both the

`ClearPortFeature` and `SetPortFeature` switch statements, it modifies

`max3421_hcd->port_status` by left shifting 1 by the request's `value`

parameter. However, it does not validate whether this shift will exceed

the width of `port_status`.

So if a malicious userspace task with access to the root hub via

/dev/bus/usb/.../001 issues a USBDEVFS_CONTROL ioctl with `wValue`

greater than or equal to 32, the left shift operation invokes

shift-out-of-bounds undefined behavior. This results in arbitrary

bit corruption of `port_status`, including the normally-immutable

change bits, which can bypass internal state checks and confuse the

hub status.

Fix this by rejecting requests whose `value` exceeds the shift width

before perf

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