Webhooks + Ports


After playing around with the webhooks functionality of the API, it seems that registering a webhook and specifying a port (i.e."url": "https://example.com:8088/webhook") causes the webhook not to fire at all. If I register a webhook that’s identical just without the port so that it fires to port 443 then it works perfectly.

Is this intentional or is it a bug?


I wonder if for security reasons they have a firewall that blocks outbound connections on non-standard ports on the machine originating the webhooks, so the webhook attempts to fire but never succeeds.


I wonder what the security risk could be though. At the end of the day it’s just a HTTP post request to a custom URL. Why should it matter which port it goes to?

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My best guess would be that being a financial organisation, all traffic probably passes through a proxy for audit purposes. Hence the block on traffic all except 80 & 443.

That’s fair enough - working for one myself I can understand that :slight_smile: I’m just looking for confirmation from Monzo mostly!