You dirty RAT: Trend Micro spots new Asia-wide attack
Security researchers are warning of yet another advanced, large-scale attack campaign using sophisticated techniques to hide itself from its targets – organisations across Asia.
Trend Micro has dubbed the campaign Naikon, based on the HTTP user-agent string “NOKIAN95/WEB” found in various targeted attacks across the region in India, Malaysia, Singapore, and Vietnam and elsewhere.
The attacks begin in time-honoured fashion with a spear-phishing email “using messages related to diplomatic discussions in the Asia Pacific region”, according to Trend Micro threat analyst Maharlito Aquino.
Targets range from governments to media, oil and gas, telecommunications and other organisations.
The malicious email attachment exploits CVE-2012-0158 – a vulnerability in Windows Common Controls which was also used in the “Safe” campaign discovered by researchers last month and thought to be connected to the “cyber criminal underground in China”.
When the attachment is opened all the victim sees is a “decoy document”, however in the background the BKDR_RARSTONE Remote Access Tool (RAT) is being dropped onto the user’s machine.
First discovered back in February and used subsequently in email attacks using the Boston Marathon Bombings as a subject line lure, RARSTONE uses several techniques to evade detection by traditional security tools, Aquino said.
The RAT loads its backdoor component from a CC server directly into memory, hiding it from traditional file-based scanners, for example.
What makes RARSTONE unique from PlugX – and other RATs – is its ability to get installer properties from Uninstall Registry Keys. This is so that it knows what applications are installed in the system and how to uninstall them, in the case that these applications inhibit RARSTONE’s functions. It also uses SSL to encrypt its communication with its CC server, which not only protects that connection but also making it blend in with normal traffic.
The attackers also aimed to hide their efforts from the likes of Trend Micro by using either dynamic DNS domains or registrars with privacy protection, he said.
There’s no info on exactly what the attackers were looking for in their campaign, although BKDR_RARSTONE is apparently capable of all the usual backdoor tricks, including “enumerating files and directories, downloading, executing, and uploading files, and updating itself and its configuration”.
Trend Micro urged organisations to bolster their defences against such attacks by supplementing blacklisting and perimeter-based controls with file integrity monitoring and other tools which can offer greater insight into network traffic to identify suspect behaviour. ®