Lavi Lazarovitz said in a blog post that the attack, which had been given the name Operation Soft Cell, was similar to that described by NSA whistleblower Edward Snowden as being used for Operation Socialist – a bid by spies from the CIA and the British General Communications Headquarters to take control of Belgian telecommunications firm Belgacom.
Neither of these attacks needed to exploit vulnerabilities or use sophisticated and aggressive tools which cost a lot to develop, Lazarovitz said.
"In both cases, the groups compromised the organisation’s privileged accounts – namely domain admin accounts. Domain admin accounts have administrator rights over an entire domain, making them extremely useful to an attacker," he said.
He said domain admin accounts and other well-known privileged accounts were usually tightly-controlled and monitored.
"However, there were still vulnerabilities to exploit. The attackers probably went after shadow admins, which are privileged accounts that aren’t members of the privileged Active Directory group, letting them fly under the radar and often go overlooked by organisations’ security teams.
"These type of accounts have special privileges that allow an attacker to gain control of a complete network control without being a member of a privileged group. Consequently, the attack leaves little trace, while still providing the attacker with flexibility. In the Soft Cell operation, the attackers launched a VPN service to allow them shadow access to the network – possibly based on shadow admin accounts."
Both Operation Socialist and Operation Soft Cell targeted the supply chain, Lazarovitz noted, adding that just as in hardware manufacturing facilities, software firms that provided product updates or Internet traffic backbone servers were vulnerable to supply chain attacks.
"This has become common, with many attackers redirecting their efforts from well-defended organisations to their less-secure supply chains," he said.
"Attackers who want intimate and persistent access to a company’s data and IP can replace sending phishing emails to vast numbers of employees with bugging the company’s hardware. Attackers who want access to an individual’s metadata, location and calls for a longer period, can replace exposing a costly WhatsApp vulnerability with compromising a specific individual’s phone."