Tavern drink, we hear, for one with access to confidential information (7)
I believe the answer is:
insider
'to confidential information' is the definition.
(thesaurus)
'tavern drink we hear' is the wordplay.
'tavern' becomes 'in' (I can't justify this - if you can you should give a lot more credence to this answer).
'drink' becomes 'cider' (cider is a kind of drink).
'we hear' shows a homophone (sound like).
'cider' is a homophone of 'sider'.
'in'+'sider'='INSIDER'
'for one with access' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for insider that I've seen before include "One dealing illegally" , "one's not allowed to trade" , "Person privy to information within an organisation" , "person in the club" , "Privileged member of a group" .)