OPC UA for Rust is still ongoing development so security is addressed in the form of raising issues or contacting the author.

Vulnerabilities will be patched in the master branch and potentially the last released branch depending on the severity and nature of the issue.

If you have a security issue, raise an open issue with the "security" label or contact the author at locka99 @AT@ gmail.com. Issue should describe the cause for concern, a way to reproduce the issue and preferably a proposed fix.