In recent OilRig attacks, the threat actors purport to be legitimate service providers offering service and technical troubleshooting as a social engineering theme in their spear-phishing attacks. Earlier OilRig attacks appear to use fake job offers as a social engineering theme. The campaign appears highly targeted and delivers a backdoor we have called ‘Helminth’. Over the course of the attack campaign, we have observed two different variations of the Helminth backdoor, one written in VBScript and PowerShell that was delivered via a macro within Excel spreadsheets and the other a standalone Windows executable.