A new Microsoft 365 phishing-as-a-service platform called "FlowerStorm" is growing in popularity, filling the void left behind by the sudden shutdown of the Rockstar2FA cybercrime service.
First documented by Trustwave in late November 2024, Rockstar2FA operated as a PhaaS platform facilitating large-scale adversary-in-the-middle (AiTM) attacks targeting Microsoft 365 credentials.
The service offered advanced evasion mechanisms, a user-friendly panel, and numerous phishing options, selling cybercriminals access for $200/two weeks.
According to Sophos researchers Sean Gallagher and Mark Parsons, Rockstar2FA suffered from a partial infrastructure collapse on November 11, 2024, making many of the service's pages unreachable.
Sophos says this does not appear to be the result of law enforcement action against the cybercrime platform but rather a technical failure.
A few weeks later, FlowerStorm, which first appeared online in June 2024, started quickly gaining traction.
Sophos has found that the new service, FlowerStorm PhaaS, shares many features previously seen in Rockstar2FA, so it is possible that operators rebranded under a new name to reduce exposure.
Sophos identified several similarities between Rockstar2FA and FlowerStorm, suggesting a shared ancestry or operational overlap:
"We cannot with high confidence link Rockstar2FA and FlowerStorm, other than to note that the kits reflect a common ancestry at a minimum due to the similar contents of the kits deployed," concludes Sophos.
"The similar patterns of domain registration could be a reflection of FlowerStorm and Rockstar working in coordination, though it is also possible that these matching patterns were driven by market forces more than the platforms themselves."
Whatever the story is behind FlowerStorm's sudden rise, for users and organizations, it's yet another enabler of damaging phishing attacks that could lead to full-blown cyberattacks.
Sophos' telemetry shows that roughly 63% of the organizations and 84% of users targeted by FlowerStorm are based in the United States.
The most targeted sectors are services (33%), manufacturing (21%), retail (12%), and financial services (8%).
To protect against phishing attacks, use multi-factor authentication (MFA) with AiTM-resistant FIDO2 tokens, deploy email filtering solutions, and use DNS filtering to block access to suspicious domains like .ru, .moscow, and .dev.