New LuckyCat-Linked RAT Targets Users in Tibet

A malware attack using a newly discovered backdoor has been targeting the mailing list of the organization officially representing the Tibetan government-in-exile.

Dubbed ExileRAT, the malware was being delivered via a malicious Microsoft PowerPoint document, using a mailing list run by the Central Tibetan Administration (CTA). Given the nature of the threat and the targets, the campaign was likely designed for espionage purposes, Talos’ security researchers say. 

The malicious PPSX document (a copy of a legitimate PDF available on CTA’s website) was sent to all subscribers to the CTA mailing list, Talos reports. The standard Reply-To header used by the CTA mailings was modified to redirect responses to the attackers’ email address.

The document exploits CVE-2017-0199, an arbitrary code execution vulnerability in Office. The file also attempts to perform some geo-location lookups and contacts the command and control (C&C) server to receive a JavaScript script responsible for downloading the final payload. 

The malware is executed via WScript, while cmd.exe also is used to create a scheduled task aiming to avoid detection. Once up and running, the malware performs an IP location lookup and writes the data to a c:data.ini file.

ExileRAT is a simple remote access Trojan platform that can retrieve system information (computer name, username, listing drives, network adapter, and process names), receive and exfiltrate files, and execute or terminate processes.

According to Talos, the infrastructure used for C&C has been used in multiple campaigns, including recent attacks featuring a newer version of the LuckyCat Android RAT used in 2012 attacks against Tibetan activists. 

The new backdoor variant includes old capabilities such as file uploading, downloading, information stealing and remote shell, but also adds file removal, app execution, audio recording, and the stealing of personal contacts, SMS, calls, and location. 

The newly observed campaign is another “evolution in a series of attacks targeting a constituency of political supporters, and further evidence that not all attacks require the use of zero-day vulnerabilities,” Talos says. 

Given that the PPSX document was using a two-year old vulnerability to download the final payload, the defensive best-practice of patching systems against known vulnerabilities should keep users secure, the security researchers point out. 

Related: Cyber-Espionage Campaigns Target Tibetan Community in India

Related: PowerPoint Slide Show Files Used to Install Malware

Original author: Ionut Arghire