The Office of the Data Protection Commissioner and other relevant bodies have been notified of the breach.
While there’s no evidence that the attackers have gained access to other systems or to customer information, as a precaution, email users are being advised to change their passwords now and on a regular basis in the future.
The company is still working on determining the origin of the breach. In an update posted around two hours ago, Eircom informed customers that webmail access had been restored. All the emails that didn’t reach their destination due to the shutdown of the service should have been delivered by now.
Users who have questions about the incident can contact the company via its Twitter account, via the online chat service, or by calling 1901.