RFC7643 §2.3.6 indicates that binary fields should be encoded in base64.
The attribute value MUST be base64 encoded as
specified in [Section 4 of [RFC4648]](https://datatracker.ietf.org/doc/html/rfc4648#section-4). In cases where a URL-safe
encoding is required, the attribute definition MAY specify that
base64 URL encoding be used as per [Section 5 of [RFC4648]](https://datatracker.ietf.org/doc/html/rfc4648#section-5). Unless
otherwise specified in the attribute definition, trailing padding
characters MAY be omitted ("=").
There should be validators and serializers for that.
RFC7643 §2.3.6 indicates that binary fields should be encoded in base64.
There should be validators and serializers for that.