Azure RTOS USBX is a USB host, device, and on-the-go (OTG) embedded stack. In versions prior to 6.1.10, an attacker can cause a buffer overflow by providing the Azure RTOS USBX host stack a HUB descriptor with `bNbPorts` set to a value greater than `UX_MAX_TT` which defaults to 8. For a `bNbPorts` value of 255, the implementation of `ux_host_class_hub_descriptor_get` function will modify the contents of `hub` -> `ux_host_class_hub_device` -> `ux_device_hub_tt` array violating the end boundary by 255 - `UX_MAX_TT` items. The USB host stack needs to validate the number of ports reported by the hub, and if the value is larger than UX_MAX_TT, USB stack needs to reject the request. This fix has been included in USBX release 6.1.10.
The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow.
| Link | Tags |
|---|---|
| https://github.com/azure-rtos/usbx/security/advisories/GHSA-2qc5-385m-x862 | third party advisory release notes |
| https://github.com/azure-rtos/usbx/releases/tag/v6.1.10_rel | third party advisory release notes |