Given access having confessed (8)
I believe the answer is:
admitted
'confessed' is the definition.
(synonyms)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for admitted that I've seen before include "Owned up or let in" , "Allowed in or accepted as true" , "Acknowledged to be true" , "Conceded; let in" , "Allowed to enter or owned up" .)