Ransomware perpetrators have stepped up their targeting of Australia with campaigns built around ransomware-laced messages purportedly from police and postal authorities, security firm ESET has reported as industry figures suggest the rising tide of ransomware attacks against Australian targets is showing no signs of abating.
The Australian Federal Police, Australia Post, AGL and New Zealand Post were all named in an analysis of ransomware attack techniques by security researchers at ESET, who reported “highly localised” landing pages that mask the deception until well after the ransomware code had been clicked on and executed.
Utilities and government bodies such as Austria's A1 Telekom, Spain's Correos, Poland's PGE Polska and Sweden's Telia figured highly in the analysis of ransomware techniques, which found that TorrentLocker ransomware – which infected over 9000 Australian PCs in late 2014 – was proving resurgent even today.
New figures from Trend Micro hinted at the extent of the ransomware scourge, with more than 1.1 million ransomware threats detected in Australia during the first half of this year alone. Trend Micro reported a 172 percent increase in ransomware infections overall, with $US3 billion ($A4b) in business losses and 79 new ransomware families identified during the first half of the year.
The latest TorrentLocker strains build on the attack's early success, adding protections such as geoblocking to ensure that infectious URLs are only accessible from the countries they are targeting. Command-and-control traffic is encrypted and obfuscated, with even the choice of which files to encrypt reflecting a stronger, more far-reaching approach on the part of the ransomware perpetrators.
“These newer TorrentLocker variants have really upped the ante,” said ESET senior research fellow Nick FitzGerald in statement. “Earlier variants, just like other crypto-ransomware, encrypted files of specific types, as determined by their filename extension.”
“The recent variants turn that approach on its head, encrypting all files except for a few types necessary to allow the system to keep working after the file system has been encrypted. This new approach to encrypting nearly all files on a system will have ramifications for the kind of backups needed to properly restore a system that has been encrypted by TorrentLocker.”
A good backup regimen has long been recognised as a key tool for protecting against ransomware, but with real-world backup practices varying widely there has still been ample opportunity for ransomware to cause major problems for its victims. FitzGerald recommends a range of other techniques that can help companies deal with ransomware when it strikes.