Storm-0940 Leverages AI Agents to Infiltrate ConnectWise Ecosystem

The rapid deployment of artificial intelligence in cyberattacks has created a new layer of tension between offensive speed and defensive response times. A recent large-scale supply chain attack demonstrates how automated agents can exploit credential theft to move through enterprise networks with alarming efficiency. This incident highlights the shifting landscape of digital threats facing organizations in the Mid-Atlantic and beyond.

Microsoft identified the attacker as Storm-0940, a China-state aligned group active since 2021. The actor utilized ARTEX, an open-source framework for agentic penetration testing, to execute the breach. After gaining unauthorized access to the multi-tenant ConnectWise application, the group attempted sign-ins at more than 2,250 Microsoft 365 tenants. They used stolen credentials that authenticated as applications, bypassing the need for interactive user sign-ins.

The speed of the operation was a defining feature of the attack. In some instances, the group achieved privileged access in less than three hours after initial targeting. The use of LLM-driven agents allowed for autonomous scanning and reconnaissance. These agents operated continuously with minimal human interaction, a pace that left defenders with little time to detect and respond to the intrusion.

The campaign also involved automated password guessing, or password spraying, which targeted 327 accounts across eight organizations. This effort generated more than 151,000 failed logons without a single success. At its peak on October 11, the spraying activity reached 2,900 attempts per minute. Almost 98 percent of this activity resulted in account lockouts, indicating a high volume of automated probes against the target systems.

Contextual analysis reveals that the attack targeted specific sectors, including aerospace and defense, semiconductor manufacturing, government entities, and think tanks. Fourteen industries were listed in total. Microsoft confirmed that the activity did not stem from a vulnerability in its own systems but rather from the compromise of the ConnectWise application identities. The sweeping nature of the attacks, which moved through tenants in sorted order with seconds between actions, suggested the use of a script working from a predefined target list.

Security firm Huntress observed the agents adding themselves to top administrator roles in at least one tenant on October 15. This behavior triggered alerts for applications self-assigning global administrator roles. By October 16, unauthorized sign-ins were confirmed for 162 tenants, a number that grew to nearly 1,000 the following day. The attackers also planted new secrets set to expire in 2028, a tactic designed to maintain long-term access.

ConnectWise responded by suspending its Cloud Backup, SaaS Security, and Cloud Management services as a precautionary measure. The company has initiated a phased restoration process, with full recovery expected to take several days. There are currently no indicators that partner backup data was compromised. Microsoft advises customers to keep affected app connections disabled and to review activity logs from this month where possible.

The incident marks a significant evolution in threat tactics, as ARTEX can utilize any AI model. Public reporting this month has linked the framework to breaches at South Korean financial institutions. The developer of ARTEX, identified by the handle Autumn-27, announced that the project will no longer be updated and will become closed source. This move may influence how other threat actors adapt their strategies in the coming months.