In their example, the OilRig group used a malicious macro document to deliver the backdoor, which is a tactic much more commonly used by them. A closer examination revealed the obfuscation used by the OilRig group in these QUADAGENT samples were likely the result of using an open-source toolkit called Invoke-Obfuscation. Invoke-Obfuscation has proven to be highly effective at obfuscating PowerShell scripts and in this case, the adversary was able to take advantage of the tool for increased chances of evasion and as an anti-analysis tactic. Based on our telemetry, we have high confidence the email account used to launch this attack was compromised by the OilRig group, likely via credential theft. The malicious attachment was a simple PE file (SHA256: 5f001f3387ddfc0314446d0c950da2cec4c786e2374d42beb3acce6883bb4e63) with the filename &lt;redacted&gt; Technical Services.exe. Its sole purpose here is to install the QUADAGENT backdoor and execute it. Once the victim downloads and executes the email attachment, it runs silently with no additional decoy documents or decoy dialog boxes. The executable will drop the packaged QUADAGENT PowerShell script using the filename Office365DCOMCheck.ps1 in addition to a VBScript file with the same filename which will assist in the execution of it. Once the QUADAGENT payload has executed, it will use rdppath[.]com as the C2, first via HTTPS, then HTTP, then via DNS tunneling, each being used as a corresponding fallback channel if the former fails