The new threat took its name from Greek mythology, as the Kovaloi were cunning, tiny followers of Dionysus.
ESET researchers discovered Kobalos, a malware that attacks supercomputers - clusters computers high performance (HPC). ESET has worked with the CERN Computer Security Group and other organizations involved in tackling attacks on scientific research networks. Among the targets were a major Internet Service Provider (ISP) in Asia, an endpoint security solutions provider in North America, as well as several private servers.
ESET researchers have worked through reverse engineering (reverse engineering ) this small but sophisticated malware that is portable to many operating systems, including Linux, BSD, Solaris, and possibly AIX and Windows.
"We named this malware Kobalos because of the small size of the code and the cunning methods it uses. In Greek mythology, Kovalos is a small, cunning creature ", explains Marc-Etienne Léveillé, who studied Kobalos. "It should be noted that this level of complexity rarely occurs in Linux malware," adds Léveillé.
Kobalos is a backdoor that contains commands which do not reveal the intent of the attackers. "In short, Kobalos provides remote file system access, terminal session replay, and allows proxy connections to other Kobalos-infected servers," says Léveillé.
Any server infected with Kobalos can be converted to a Command & Control (C&C) server with a single command from the operators. As the IP addresses and ports of the C&C server are integrated into the executable program, operators can then create new samples of Kobalos using this new C&C server. In addition, on most systems infected with Kobalos, the SSH client steals credentials.
“The credentials of those using the SSH client on an infected machine καταγράφονται. Αυτά τα διαπιστευτήρια μπορούν στη συνέχεια να χρησιμοποιηθούν από τους εισβολείς για να εγκαταστήσουν το Kobalos στο νέο server», προσθέτει ο Léveillé. Η δημιουργία ελέγχου ταυτότητας δύο παραγόντων για connection on SSH servers will mitigate the threat, as using stolen credentials appears to be one of the ways it can spread to different systems.
More technical details about Kobalos can be found at blogpost “Kobalos - A complex Linux threat to high performance computing infrastructure”At WeLiveSecurity.
