CVE-2022-29246: azure-rtos usbx Classic Buffer Overflow

Vulnerability summary

CVE-2022-29246 is a critical (CVSS 9.8) Classic Buffer Overflow vulnerability in azure-rtos usbx. EPSS estimates a 2.42% chance of exploitation in the next 30 days, higher than 83.9% of scored vulnerabilities.

Timeline

1. 24-05-2022
   PublishedVulnerability first disclosed.
2. 23-04-2025
   Last modifiedVulnerability information updated.

Description

Azure RTOS USBX is a USB host, device, and on-the-go (OTG) embedded stack. Prior to version 6.1.11, he USBX DFU UPLOAD functionality may be utilized to introduce a buffer overflow resulting in overwrite of memory contents. In particular cases this may allow an attacker to bypass security features or execute arbitrary code. The implementation of `ux_device_class_dfu_control_request` function does not assure that a buffer overflow will not occur during handling of the DFU UPLOAD command. When an attacker issues the `UX_SLAVE_CLASS_DFU_COMMAND_UPLOAD` control transfer request with `wLenght` larger than the buffer size (`UX_SLAVE_REQUEST_CONTROL_MAX_LENGTH`, 256 bytes), depending on the actual implementation of `dfu -> ux_slave_class_dfu_read`, a buffer overflow may occur. In example `ux_slave_class_dfu_read` may read 4096 bytes (or more up to 65k) to a 256 byte buffer ultimately resulting in an overflow. Furthermore in case an attacker has some control over the read flash memory, this may result in execution of arbitrary code and platform compromise. A fix for this issue has been included in USBX release 6.1.11. As a workaround, align request and buffer size to assure that buffer boundaries are respected.

• CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')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.