2.3.1 ms-DS-Issuer-Certificates
The ms-DS-Issuer-Certificates attribute is a multivalued OCTET_STRING attribute (see [MS-ADTS] section 3.1.1.2.2.2, the String(Octet) syntax). Each value of the attribute is stored as a binary blob containing the following formatted data:
[time]:[binary value of an X.509 certificate]
where [time] is the timestamp formatted as an integer representing the number of 100-nanosecond intervals that have elapsed since 12:00:00 midnight, January 1, 0001, UTC, and [binary value of an X.509 certificate] is the contents of an X.509 certificate [RFC5280] stored as an encrypted binary blob.