At least three UK VoIP providers have been hit by a DDoS attack, according to the Cloud Communications Alliance (CCA).
In an email sent this morning, CCA said it has learned of a “sophisticated, specific and ongoing attack”, believed to be from Russian cybercriminal organisation REvil.
Two providers revealed they were victims of the attack last week, but the third company was not named by CCA.
Poole-based Voip Unlimited said the attack on its core network started on 31 August and was continuous for 75 hours. An update from this firm this morning said it did not observe any further attacks over the weekend.
London-based Voipfone reported its attack at the same time and said this morning that its services are fully operational, with traffic being closely monitored.
Both firms saw their services disrupted over the three-day period.
CCA said that the culprits were demanding ransom, starting at 1 Bitcoin but quickly increasing.
