Can anybody extract the payment ID from an integrated address?

Oh no, it's encrypted by the transaction shared secret, right?

integrated address is easy to extract

integrated_address <address>

unless I misunderstand your question

Wait, I'm not sure if I understand my question

I'm trying to make senses of how CloakVPN works

It generates a random Payment ID to use as credentialss

Then provides an integrated address

yep

it is not encrypted, it just requires you to not share your payment id

If I send a transaction with that integrated address `4Bcu...h4bw`can an outside observer extract the payment ID `1570...8757`?

no

it is encrypted on chain, but if you share an integrated address everyone can extract the payment id

Ah I see what you mean now

So besides the small search space for credentials, this is theoretically secure with respect to outside blockchain observers