Composio Agent Integration Platform Breach Exposes 10,000+ Customer Credentials

Composio, an integration platform that brokers third-party tool access for AI agents

Attackers exfiltrated 5,241 API keys and 5,001 GitHub OAuth tokens, plus 12 Gmail tokens and smaller numbers of Jira, Slack, HubSpot, Linear, Notion, and Google Calendar tokens, for a total above 10,000 customer credentials. Because Composio's role is to hold downstream credentials on behalf of customer agents, a single breach of the broker handed the attacker working access to the connected services of every affected customer

A compromised Gmail OAuth token belonging to a Composio employee gave the attacker inbox access, which was used to intercept magic-link sign-in emails. From there the attacker registered malicious tool definitions to obtain arbitrary code execution in the sandbox and reached the production credential cache. The same OAuth-token pivot pattern as the Vercel and Context.ai chain a month earlier