With signed attributes, the signature value is made over the attributes,
and their messageDigest is what ties it to the document. The digest was
compared only when the attribute was present, and the content-type
attribute was never checked. RFC 5652 section 5.3 requires both.
A signature whose signed attributes have no messageDigest, or name a
content type other than id-data, is now invalid. A missing content type
is reported and the signature is read anyway. A signature that still
validates with an RSA key under 2048 bits now gets a note, as SHA-1 and
RIPEMD-160 do. The four new sentences are in WORDINGS and in Spanish.