AI Agents Smash ConnectWise Security

Storm 0940, a hacking group aligned with the Chinese state, executed a massive supply chain attack by deploying ARTEX. This open source framework utilizes agentic AI to conduct autonomous penetration testing. Microsoft reported that the group leveraged this technology to breach ConnectWise, a multi tenant application. The attackers then used stolen credentials to authenticate as applications rather than individual users. This method allowed them to attempt sign ins across more than 2,250 Microsoft 365 tenants without requiring interactive user login.

The scale of the automated assault was significant. Password spraying campaigns targeted 327 accounts across eight organizations. These efforts generated over 151,000 failed logons with zero successes. At its peak on October 11, the system executed 2,900 attempts per minute. This resulted in more than 111,000 failures in a single day. Forty eight accounts logged more than 1,000 failures each. Nearly 98 percent of this activity was locked out. However, the AI agents signed into customer tenants from the same IP range using stolen application credentials. They achieved more than 200 sign ins in under four minutes using just four application credentials.

The involvement of specific firms and actors clarifies the threat landscape. Huntress, a security firm, observed an application adding itself to the top administrator role in one tenant on October 15. This action triggered a Microsoft Defender alert regarding global administrator role self assignment. The attackers planted new secrets set to expire in 2028. By October 16, Huntress confirmed unauthorized sign ins for 162 tenants. A day later, nearly 1,000 Entra tenants showed sign in activity from the attacking IP address. More than 300 of these attempts succeeded. The sequential nature of the sweep indicated a script working from a pre defined target list.

Storm 0940 has been active since 2021 and holds no known industry aliases. The group targeted industries including aerospace and defense, semiconductor, government, and think tanks. Fourteen specific sectors were listed in the attack scope. Microsoft clarified that the activity did not stem from a vulnerability in its own systems or products. The use of ARTEX sped up scanning, reconnaissance, and OAuth application abuse. The agents operated with little human interaction, leaving defenders with minimal time to react. Some attacks reached privileged access within three hours of initial targeting.

The broader implications involve the rise of AI in cyber operations. CrowdStrike noted that a suspect in separate breaches at South Korean financial institutions likely used ARTEX with Anthropic's Claude Code. The developer of ARTEX, known as Autumn 27, announced on GitHub that the project will stop being updated and become closed source. ConnectWise has suspended its Cloud Backup, SaaS Security, and Cloud Management services as a precaution. A phased restoration is underway, with recovery expected to take several days. The company reported no indicators that partner backup data was compromised. Microsoft advises customers to keep affected app connections disabled until formal restoration instructions are issued.