It was so good at its job, and so stealthy that it went completely undetected for years. That gave the hackers controlling it a convenient access point literally for years.
Based on the company's research, the first sample they could find of the malicious code they dubbed RotaJakiro, was uploaded in 2018. It took more than three years for anyone to become aware of its existence, and in the computer world, three years is just shy of eternity.
A Qihoo spokesman had this to say about the recent discovery:
"At the functional level, RotaJakiro first determines whether the user is root or non-root at run time, with different execution policies for different accounts, then decrypts the relevant sensitive resources using AES& ROTATE for subsequent persistence, process guarding and single instance use, and finally establishes communication with C2 and waits for the execution of commands issued by C2.
RotaJakiro supports a total of 12 functions, three of which are related to the execution of specific Plugins. Unfortunately, we have no visibility to the plugins, and therefore do not know its true purpose."
In all, the company's researchers discovered four code samples online, all of them dating back to 2018, and none of them having ever been detected before Qihoo discovered them.
Of interest, RotaJakiro seems to have code in common with the Torii IoT botnet. That botnet was discovered by Vesselin Bontchev in September of 2018 and analyzed in depth by the Threat Intelligence Team run by Avast. Torii and RotaJakiro share a number of similarities including "the use of encryption algorithms to hide sensitive resources, the implementation of a rather old-school style of persistence, structured network traffic."
In any case, this isn't a widespread, pervasive threat, so odds are that you'll never actually run across it. Even so, it's an interesting bit of code to be aware of.