ESET: China-linked cyberespionage group APT15 has been using a previously undocumented backdoor for more than two years. The group has been active since at least 2010, it conducted cyber espionage campaigns against targets worldwide in several industries, including defense, high tech, energy, government, aerospace, and manufacturing. ESET has not been able to discover the initial attack vector and the dropper of the malware, anyway the experts have identified the components used in the Okrum backdoor: an optional stage 0 loader; stage 1 loader; an installer component; a PNG file with an embedded backdoor;”]
Source: https://securityaffairs.co/wordpress/88824/apt/apt15-okrum-backdoor.html