ChamelDoH: New Linux Backdoor Utilizing DNS-over-HTTPS Tunneling for Covert CnC
Jun 16, 2023
Endpoint Security / Network Security
 The threat actor known as  ChamelGang  has been observed using a previously undocumented implant to backdoor Linux systems, marking a new expansion of the threat actor's capabilities.  The malware, dubbed  ChamelDoH  by Stairwell, is a C++-based tool for communicating via DNS-over-HTTPS ( DoH ) tunneling.  ChamelGang was  first outed  by Russian cybersecurity firm Positive Technologies in September 2021, detailing its attacks on fuel, energy, and aviation production industries in Russia, the U.S., India, Nepal, Taiwan, and Japan.  Attack chains mounted by the actor have leveraged vulnerabilities in Microsoft Exchange servers and Red Hat JBoss Enterprise Application to gain initial access and carry out data theft attacks using a passive backdoor called DoorMe.   "This is a native  IIS module  that is registered as a filter through which HTTP requests and responses are processed," Positive Technologies said at the time. "Its principle of operation ...