Security Week reports:A previously unknown, modular malware family that targets Linux systems has been used in targeted attacks to collect credentials and gain access to victim systems, ESET reported on Thursday. Dubbed FontOnLake, the malware family employs a rootkit to conceal its presence and uses different command and control servers for each sample, which shows how careful its operators are to maintain a low profile. What's more, the malware developers are constantly modifying the FontOnLake modules, and use three categories of components that have been designed to work together, namely trojanized applications, backdoors, and rootkits. Evidence suggests that FontOnLake has been used in attacks aimed at organizations in Southeast Asia. The first malware samples related to this family emerged last May. The malware was previously described by Avast and Lacework as the HCRootkit / Sutersu Linux rootkit, as well as by Tencent Security Response Center in a February report. The various trojanized applications that ESET's researchers have identified during their investigation are used to load custom backdoor or rootkit modules, but also to collect sensitive data when needed. Posing as standard Linux utilities, these files were also designed to achieve persistence on the compromised systems. What the researchers haven't figured out yet is the manner in which the trojanized applications are delivered to the victims. ESET's analysis of FontOnLake has revealed the use of three different backdoors, all written in C++, all using the same Asio library from Boost, and all capable of exfiltrating sshd credentials and bash command history. The simplest of the three was designed to launch and mediate access to a local SSH server, update itself, and transmit collected credentials. The malware appears to be under development. The second backdoor was also capable of file manipulation, updating itself, and uploading and downloading files, according to the article, while the third backdoor "accepts remote connections, serves as a proxy and can download and run Python scripts, in addition to exfiltrating credentials."Read more of this story at Slashdot. Click here to read full news..