Attribute size is validated in number of characters, not bytes

[hablutzel1]

From RFC 5280, "Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile", "4.1.2.4. Issuer":

The type of the component AttributeValue is determined by the AttributeType;
in general it will be a DirectoryString.

From ITU-T Rec. X.680 (11/2008), "Information technology – Abstract Syntax Notation One (ASN.1): Specification of basic notation", "51.5 Size constraint":

51.5 Size constraint
...
51.5.4 The unit of measure depends on the parent type, as follows:
Type               Unit of measure
bit                  string bit
octet              string octet
character     string character
set-of             component value
sequence-of   component value