Malware Analysis Space

  Summary Mirai botnet family first discovered in 2016, the botnet will look for devices of IoT with scanner which embedded a dictionary for brute force attack and vulnerabilities exploit, and can do a DDoS attack like TCP flood and UDP flood and so on, later on, the source code distributed in github and different variants came from that time, nowadays, botnet is big challenging and threat to IoT, it is worthy doing research with different instruction sets, this report come here for a new try and let’s do it.     Technical analysis   This botnet is the ELF for Intel 386 (executable). The hash MD5:  6950F28382D7F11E18BDF53F3983117B The load segment displays lots of source files that can help analysts to learn from which source code is being included and infer the main function of malware, likely with the source file “kill.c” to tell the analyst it may use the kill command to stop the process and “socket.c,” which can be used for malware to conne...

  Summary Since 2016, when the Mirai source code was published, similar family botnets have emerged; more and more botnets have appeared. and IoT security has become a big challenge. That makes me care about botnet development and do research. Recently, Mirai attracts me again; I like to do analysis with it in a different way, so here it is.   Analysis   Protect and Disguise Itself Like any other malware that does anti-debug from an analyst, Mirai uses the function anti_gdb_entry with one parameter to monitor gdb debug. If it discovers debugging, it executes the function unlink to delete itself and tries to prevent the watchdog from rebooting the device and keep itself running all the time, not offline. Figure1-anti-debug, delete self and keeping running   Using a random string which the length can be either 12, 16, 20, or 24 as name of processes and execute util_strcpy function for copying string to args[0] and hiding a real name. Figure2-Hide argv0 ...