Upstart rides off with password perhaps (4,1,1)

I believe the answer is:

user i d

I'm a little stuck... Click here to teach me more about this clue!

'password perhaps' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'upstart rides off' is the wordplay.
'upstart' becomes 'u' (start of the word 'up').
'off' is an anagram indicator.
'rides' is an anagram of 'serid'.
'u'+'serid'='USER I D'

'with' acts as a link.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.