Microsoft says a China-aligned group used an agentic AI pentest framework in the ConnectWise attack
Storm-0940 used the open-source ARTEX framework to try to sign in to more than 2,250 tenants, in some cases going from first targeting to privileged cloud access in under three hours.
Microsoft Threat Intelligence reported on October 21 that Storm-0940, which it describes as a China-state aligned actor, used "the agentic AI penetration testing framework ARTEX to automate attacks targeting hundreds of organizations globally." Microsoft assesses that the group was responsible for the recently disclosed ConnectWise supply chain compromise. "ARTEX is an open-source penetration testing framework that can use any AI model," Microsoft writes, and after the initial unauthorized access "Storm-0940 used ARTEX to attempt to sign-in to more than 2,250 tenants."
How fast it moved
Several attacks gave the group privileged access to an organization's cloud infrastructure, "including multiple instances where the time from initial targeting to privileged access was less than 3 hours." In a separate password-spray campaign from October 10 to 14, Microsoft recorded more than 151,000 failed logons, "with activity peaking on October 11 at 2,900 failures per minute." Microsoft says the activity did not come from a vulnerability in its own systems, and that an affected application or a successful sign-in does not by itself mean customer data was accessed.
Why it matters
The attack worked through applications that already had access to Microsoft 365 tenants, so no interactive user sign-in was needed. Every AI tool and agent you connect to company data is another application of that kind. When you count what an AI rollout costs, include reviewing which apps hold standing access, and how fast you could revoke it, because an attacker using agents will not wait for a weekday.