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 performing the shift.
This issue was found using a KLEE-based symbolic execution tool for
kernel drivers that I'm currently developing.
Analysis and contextual insights are available on OpenCVE Cloud.
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Sat, 15 Aug 2026 19:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-680 |
Sat, 15 Aug 2026 06:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| 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 performing the shift. This issue was found using a KLEE-based symbolic execution tool for kernel drivers that I'm currently developing. | |
| Title | usb: host: max3421: Fix shift-out-of-bounds in max3421_hub_control() | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-08-15T05:57:20.914Z
Reserved: 2026-08-09T03:40:39.935Z
Link: CVE-2026-72483
No data.
Status : Received
Published: 2026-08-15T06:22:22.527
Modified: 2026-08-15T06:22:22.527
Link: CVE-2026-72483
No data.
OpenCVE Enrichment
Updated: 2026-08-15T18:45:03Z
-
CWE-680
Integer Overflow to Buffer Overflow