LibreSSL 3.5.3 was released on May 18th, 2022.
The release notes may be found here:
However, given the release notes are rather brief, they are quoted here in their entirety:
We have released LibreSSL 3.5.3, which will be arriving in the LibreSSL directory of your local OpenBSD mirror soon. It includes the following reliability fix: * Fix d2i_ASN1_OBJECT(). A confusion of two CBS resulted in advancing the passed *der_in pointer incorrectly. Thanks to Aram Sargsyan for reporting the issue and testing the fix. The LibreSSL project continues improvement of the codebase to reflect modern, safe programming practices. We welcome feedback and improvements from the broader community. Thanks to all of the contributors who helped make this release possible.