Commonwealth Bank customers are venting their frustration on social media after being unable to access their accounts through the bank’s app Netbank.

People trying to use Netbank are being confronted with a message that the bank ‘is working to fix an issue affecting our services’.

The message goes on to say: We’re aware some customers may be encountering difficulties with some of our services right now. We are urgently investigating this and we’re sorry for any inconvenience caused.”

It appears the app may have been down since about 8pm on Tuesday night.

Tweet from @CommBank

Website services are also affected.

It’s not clear how widespread the outage is.