Microsoft has warned that Windows devices running the latest supported processors on Windows 11 and Windows Server 2022 are vulnerable to “data corruption.”
The affected devices use AES-XTS (AES XEX-based tweaked codebook mode with ciphertext theft} or AES-GCM (AES with Galois / Counter Mode) block cipher modes on new hardware.
However, while Microsoft failed to explain what users should expect when hit by the issue, the company stated that it has been addressed in preview and security releases issued on May 24 and June 14 respectively.
The update to prevent data damage resulted in a performance hit. After installing the update, AES-based operation will be twice as slow after installation on affected systems running Windows Server 2022 and Windows 11 original version.
“We added new code paths to the Windows 11 (original release) and Windows Server 2022 versions of SymCrypt to take advantage of VAES (vectorized AES) instructions,” Microsoft explained the cause of the problem.
To work around this issue, users are advised to install the June 23 preview update (Windows 11, Windows Server 2022) or the July 12 security update (Windows 11, Windows Server 2022) for their OS version.