TrickBot Malware Gang Upgrades its AnchorDNS Backdoor to AnchorMail

Even as the TrickBot infrastructure closed shop, the operators of the malware are continuing to refine and retool their arsenal to carry out attacks that culminated in the deployment of Conti ransomware.

IBM Security X-Force, which discovered the revamped version of the criminal gang’s AnchorDNS backdoor, dubbed the new, upgraded variant AnchorMail.

AnchorMail “uses an email-based [command-and-control] server which it communicates with using SMTP and IMAP protocols over TLS,” IBM’s malware reverse engineer, Charlotte Hammond, said. “With the exception of the overhauled C2 communication mechanism, AnchorMail’s behavior aligns very closely to that of its AnchorDNS predecessor.”

The cybercrime actor behind TrickBot, ITG23 aka Wizard Spider, is also known for its development of the Anchor malware framework, a backdoor reserved for targeting selected high value victims since at least 2018 via TrickBot and BazarBackdoor (aka BazarLoader), an additional implant engineered by the same group.

Over the years, the group has also benefited from a symbiotic relationship with the Conti ransomware cartel, with the latter leveraging TrickBot and BazarLoader payloads to gain a foothold for deploying the file-encrypting malware.

“By the end of 2021, Conti had essentially acquired TrickBot, with multiple elite developers and managers joining the ransomware cosa nostra,” AdvIntel’s Yelisey Boguslavskiy noted in a report published mid-February. Read more:

Leave a Reply

Your email address will not be published. Required fields are marked *