ConnectWise breach: Microsoft says Storm-0940 used AI agents

Microsoft says AI agents used the stolen app identities

ARTEX is an open source penetration testing framework that can use any AI model to automate offensive security work.

Microsoft says the attacker took control of the identities of several ConnectWise cloud applications. Its AI agents then used them to sign in to customer environments.

After the unauthorised access, Storm-0940 used ARTEX to try to sign in to more than 2,250 tenants. In several cases, the time from first targeting to privileged access was less than 3 hours.

Microsoft says most of the targeting did not succeed. It also says an affected app, or a successful sign-in by the attacker, does not necessarily mean customer data was accessed or taken.

ConnectWise disabled the affected apps and paused services

ConnectWise says it found the problem on 14 October 2026. On 17 October 2026 it disabled seven of its application identities.

Disabling them stops new sign-ins through those connections. It does not undo changes already made inside a customer's tenant.

SaaS Security and Cloud Management are also suspended as a precaution, because they are integrated with Cloud Backup. ConnectWise says a suspension does not, by itself, mean an environment was compromised.

Existing backup archives remain encrypted, isolated and preserved, with no indication of compromise. ConnectWise has no indication that its other products are affected.

ConnectWise says that, based on its evidence and threat intelligence shared by Microsoft, a China state-aligned group appears to have been responsible.

What it means for firms that use an IT provider

The NCSC says an MSP's own systems can be a target, because attackers can use them to reach its customers' cloud services. ConnectWise makes the same point: MSPs are targets in their own right, and a path into every client they serve.

Alan Woodward wrote on LinkedIn that the degree of interconnectivity, and how one component depends on another, is so often forgotten.

If your IT provider used ConnectWise Cloud Backup, ask whether it has checked your Microsoft 365 environment. ConnectWise says reviewing each one remains essential, and Microsoft advises reviewing activity from at least 15 October 2026.

Microsoft also advises keeping the affected connections disabled until ConnectWise gives restoration instructions, and not deleting the apps as a first step.

For the longer term, the NCSC advises least privilege for your MSP, and 2-step verification on its access to your systems. It also advises contract terms on how the MSP reports incidents.

What happens next

ConnectWise gave its latest update on 23 October. It expected to finish testing the restored environment by the end of this weekend. Then it will return services to partners in phases.

It expects to let partners restore data from existing backups early next week, after testing.