ARTEX: three reports tie an AI pentest tool to intrusions

What the reports say

In October 2026 two security vendors published three reports on attacks run with ARTEX, an open-source penetration testing framework in which several language-model agents work through an attack together. Each report describes a separate campaign, and each vendor bases its account on its own data.

On 7 October CrowdStrike described a campaign against South Korean financial organisations, active from late September to early October, that it says “resulted in exfiltrated data”. It found Claude Code session histories, ARTEX configuration files and memory files in open directories on servers it links to the attacker. According to CrowdStrike, the ARTEX instance used DeepSeek v4.1-flash as its main model, and the attacker used GLM-5.3 and Grok 4.6 in other sessions. CrowdStrike does not attribute the activity to a named group; it assesses with moderate confidence that the actor is likely a Chinese speaker and financially motivated. The number of affected organisations was unconfirmed when it published.

On 21 October Microsoft attributed ARTEX-driven attacks on hundreds of organisations, from as early as September, to Storm-0940, which it describes as a China-state aligned actor active since 2021. Microsoft assesses that Storm-0940 was behind the compromise of ConnectWise’s Cloud Backup application, which ConnectWise first disclosed on 16 October. After that compromise, according to Microsoft, the actor used ARTEX to try to sign in to more than 2,250 customer tenants through the application’s existing access. In several attacks it reached privileged cloud access less than three hours after first targeting an organisation.

On 29 October CrowdStrike reported that VAPOR PANDA, a group active since 2021, used a single ARTEX controller from 17 October against more than 200 organisations in at least 14 countries, among them foreign ministries, telecoms providers and US defence, semiconductor and pharmaceutical firms. CrowdStrike says it confirmed post-exploitation activity at nine organisations and that this campaign is separate from Storm-0940’s.

How the reports compare

What ARTEX is

Microsoft describes ARTEX as an open-source, multi-agent framework written in Go with a Next.js interface. It can work with any AI model, runs a penetration test from reconnaissance to data exfiltration with little human input, and stores what it finds in a graph. CrowdStrike adds that it was developed in China, and that in the VAPOR PANDA campaign a main agent coordinated planner and worker agents. Both CrowdStrike reports map its use to MITRE ATT&CK technique T1588.007, Obtain Capabilities: Artificial Intelligence.

What changes for defenders

The reports describe familiar techniques run faster and against more targets at once: password spraying, abuse of trusted application credentials, web shells and known flaws. Microsoft notes that machine-speed activity can trigger alerts and still leave little time to respond. It also cautions that the “presence of an affected application or successful threat actor authentication does not necessarily indicate that customer data was accessed or exfiltrated”.

• Organisations that used the affected ConnectWise applications should review service-principal sign-ins and application credential changes from at least 15 October, as Microsoft advises.
• Rotate keys and credentials kept in old backups and directory exports. In one VAPOR PANDA intrusion, according to CrowdStrike, the operator gave the agent keys from a 2022 export that had likely never been rotated.

Timeline

• Late Sep 2026 The campaign against South Korean financial organisations begins, according to CrowdStrike.
• 7 Oct 2026 CrowdStrike publishes its report on that campaign.
• 10–14 Oct 2026 Storm-0940 sprays passwords at 327 accounts in eight organisations without a successful sign-in, according to Microsoft.
• 16 Oct 2026 ConnectWise publishes its first advisory on unauthorised access to Cloud Backup.
• 17 Oct 2026 VAPOR PANDA’s ARTEX activity begins, according to CrowdStrike.
• 21 Oct 2026 Microsoft attributes ARTEX-driven attacks and the ConnectWise compromise to Storm-0940.
• 29 Oct 2026 CrowdStrike publishes its VAPOR PANDA report.

What is not known

• Which organisations were breached in each campaign, and what data was taken outside the South Korean cases.
• How much of each intrusion the agents ran without a person deciding; only the VAPOR PANDA report describes the operator’s role.
• Who wrote ARTEX, and whether its authors are linked to any of the three groups.
• Whether ConnectWise or its customers accept Microsoft’s attribution.