Maximum number of entries in a SAN extension

In an AD CS Certification Authority database, the Subject Alternative Name (SAN) extension (OID 2.5.29.17) for a certificate is stored in a single row in the Extension table.
The schema for the Extension table is:



where 4096 is the maximum length of the raw extension value in bytes.
That means that in a Microsoft AD CS Certification Authority, the maximum number of SAN entries that can be added to a certificate is not constrained by the number of entries itself but by the total size of the extension, that cannot exceed 4096 bytes.

https://social.technet.microsoft.com/wiki/contents/articles/3306.pki-faq-what-is-the-maximum-number-of-names-that-can-be-included-in-the-san-extension.aspx

Update: Microsoft has now provided a way of increasing that limit to 16.384 bytes, given the required updates have been applied:

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