CVE-2022-39293
Azure RTOS USBX Host PIMA vulnerable to read integer underflow with buffer overflow
CVE-2022-39293 is a high vulnerability (CVSS 8.6) in Azure-rtos Usbx, published October 13, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.85%, the 58th percentile. No source names a fixed version.
- Severity
- 8.6 HighCVSS 3.1, CVE List
- Exploit chance
- 0.85%EPSS, 58th percentile
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
- No fix listedNo source names one
Description
Azure RTOS USBX is a high-performance USB host, device, and on-the-go (OTG) embedded stack, that is fully integrated with Azure RTOS ThreadX. The case is, in _ux_host_class_pima_read, there is data length from device response, returned in the very first packet, and read by L165 code, as header_length. Then in L178 code, there is a “if” branch, which check the expression of “(header_length - UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE) > data_length” where if header_length is smaller than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE, calculation could overflow and then L182 code the calculation of data_length is also overflow, this way the later while loop start from L192 can move data_pointer to unexpected address and cause write buffer overflow. The fix has been included in USBX release 6.1.12. The following can be used as a workaround: Add check of header_length: 1. It must be greater than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE. 1. It should be greater or equal to the current returned data length (transfer_request -> ux_transfer_request_actual_length).
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- High
Exploit likelihood
Affected products
What each source reports
CVE List Score used 8.6
Azure RTOS USBX Host PIMA vulnerable to read integer underflow with buffer overflow
Azure RTOS USBX is a high-performance USB host, device, and on-the-go (OTG) embedded stack, that is fully integrated with Azure RTOS ThreadX. The case is, in _ux_host_class_pima_read, there is data length from device response, returned in the very first packet, and read by L165 code, as header_length. Then in L178 code, there is a “if” branch, which check the expression of “(header_length - UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE) > data_length” where if header_length is smaller than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE, calculation could overflow and then L182 code the calculation of data_length is also overflow, this way the later while loop start from L192 can move data_pointer to unexpected address and cause write buffer overflow. The fix has been included in USBX release 6.1.12. The following can be used as a workaround: Add check of header_length: 1. It must be greater than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE. 1. It should be greater or equal to the current returned data length (transfer_request -> ux_transfer_request_actual_length).
- Record
CVE-2022-39293- CVSS 3.1
- 8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - Weakness
- CWE-191
- Updated
- 2026-11-02
EUVDEUVD-2022-41790 8.6
Azure RTOS USBX is a high-performance USB host, device, and on-the-go (OTG) embedded stack, that is fully integrated with Azure RTOS ThreadX. The case is, in _ux_host_class_pima_read, there is data length from device response, returned in the very first packet, and read by L165 code, as header_length. Then in L178 code, there is a “if” branch, which check the expression of “(header_length - UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE) > data_length” where if header_length is smaller than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE, calculation could overflow and then L182 code the calculation of data_length is also overflow, this way the later while loop start from L192 can move data_pointer to unexpected address and cause write buffer overflow. The fix has been included in USBX release 6.1.12. The following can be used as a workaround: Add check of header_length: 1. It must be greater than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE. 1. It should be greater or equal to the current returned data length (transfer_request -> ux_transfer_request_actual_length).
- Record
EUVD-2022-41790- CVSS 3.1
- 8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - Updated
- 2026-11-02
NVD 8.6
Azure RTOS USBX is a high-performance USB host, device, and on-the-go (OTG) embedded stack, that is fully integrated with Azure RTOS ThreadX. The case is, in _ux_host_class_pima_read, there is data length from device response, returned in the very first packet, and read by L165 code, as header_length. Then in L178 code, there is a “if” branch, which check the expression of “(header_length - UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE) > data_length” where if header_length is smaller than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE, calculation could overflow and then L182 code the calculation of data_length is also overflow, this way the later while loop start from L192 can move data_pointer to unexpected address and cause write buffer overflow. The fix has been included in USBX release 6.1.12. The following can be used as a workaround: Add check of header_length: 1. It must be greater than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE. 1. It should be greater or equal to the current returned data length (transfer_request -> ux_transfer_request_actual_length).
- Record
CVE-2022-39293- CVSS 3.1
- 8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-191
- Updated
- 2026-11-02
OSV 8.6
Azure RTOS USBX Host PIMA vulnerable to read integer underflow with buffer overflow
Azure RTOS USBX is a high-performance USB host, device, and on-the-go (OTG) embedded stack, that is fully integrated with Azure RTOS ThreadX. The case is, in _ux_host_class_pima_read, there is data length from device response, returned in the very first packet, and read by L165 code, as header_length. Then in L178 code, there is a “if” branch, which check the expression of “(header_length - UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE) > data_length” where if header_length is smaller than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE, calculation could overflow and then L182 code the calculation of data_length is also overflow, this way the later while loop start from L192 can move data_pointer to unexpected address and cause write buffer overflow. The fix has been included in USBX release 6.1.12. The following can be used as a workaround: Add check of header_length: 1. It must be greater than UX_HOST_CLASS_PIMA_DATA_HEADER_SIZE. 1. It should be greater or equal to the current returned data length (transfer_request -> ux_transfer_request_actual_length).
- Record
CVE-2022-39293- CVSS 3.1
- 8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H - Weakness
- CWE-191
- Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.