Insyde's Security Pledge
Recent Security Advisories

INSYDE-SA-2022063
Product
CVSS Score
Original Date
Last Revised
InsydeH2O
7.5
2022-11-14
Summary
In UsbCoreDxe, tampering with the contents of the USB working buffer using DMA while certain USB transactions are in process leads to a TOCTOU problem that could be used by an attacker to cause SMRAM corruption and escalation of privileges.
Vulnerability Details
CVSS Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
The UsbCoreDxe module creates a working buffer for USB transactions outside of SMRAM. The code which uses can be inside of SMM, making the working buffer untrusted input. The buffer can be corrupted by DMA transfers. The SMM code code attempts to sanitize pointers to ensure all pointers refer to the working buffer, but when a pointer is not found in the list of pointers to sanitize, the current action is not aborted, leading to undefined behavior. This issue was discovered by Insyde engineering based on the general description provided by Intel’s iSTARE group. Fixed in:
Solution Information
Kernel 5.0: Version 05.09.21
Kernel 5.1: Version 05.17.21
Kernel 5.2: Version 05.27.21
Kernel 5.3: Version 05.36.21
Kernel 5.4: Version 05.44.21
Kernel 5.5: Version 05.52.21
Acknowledgements
Revision History
Revision #
Date
Description
1
2022-11-14
Initial Release