Threat actors are abusing HTTP client tools like Axios in conjunction with Microsoft's Direct Send feature to form a "highly efficient attack pipeline" in recent phishing campaigns, according to new findings from ReliaQuest.
"Axios user agent activity surged 241% from June to August 2025, dwarfing the 85% growth of all other flagged user agents combined," the cybersecurity company said in a report shared with The Hacker News. "Out of 32 flagged user agents observed in this timeframe, Axios accounted for 24.44% of all activity."
The abuse of Axios was previously flagged by Proofpoint in January 2025, detailing campaigns utilizing HTTP clients to send HTTP requests and receive HTTP responses from web servers to conduct account takeover (ATO) attacks on Microsoft 365 environments.
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