What's being called the biggest online leak in history surfaced over the weekend, as the Süddeutsche Zeitung reported on the eleven million documents (some 2.6 terabytes of data) a whistle-blower leaked from the Panama-based law firm Mossack Fonseca. The data are said to indicate money laundering and the massive transfer of funds to offshore private accounts by a number of world leaders and senior government officials. The transfers go back more than a decade. Süddeutsche Zeitung has said that Le Monde, the BBC, and the Guardian are also involved in the investigation. Prominently mentioned in dispatches: Russian President Vladimir Putin, said to have transferred more than a billion dollars.

Elsewhere, ransomware continues to bedevil North American healthcare providers. MedStar appears to have largely returned to normal operations, and to have done so without paying ransom. US and Canadian authorities issue a joint alert about ransomware as the FBI continues its investigation of the MedStar hack. Avira reports a newish twist on criminals' methods: "Rokku's" controllers offer a QR code to make it easier for victims to make mobile payments.

Government websites in Hungary sustained a brief cyber attack by unspecified foreign actors over the weekend.

Turkish hacktivists open cyber-rioting against Armenian targets, deciding to side with Azerbaijan in the long-running dispute over the province of Nagorno-Karabakh.

The Islamic State West Africa (ISWA), the terrorist group formerly styling itself Boko Haram, has pledged fealty to ISIS leader Abu Bakr al Baghdadi. The US Justice Department warns of a coming cyber jihad.