A security researcher has uncovered five critical vulnerabilities in Azure's API Connections architecture, enabling full cross-tenant compromise. These flaws allow attackers to bypass input validation and gain unauthorized access to any connected backend service, including Azure Key Vault and SQL databases. The researcher demonstrated exploitation through the ARM REST API and Dynamic Invoke endpoints, earning $200,000 in bug bounties.
The architecture relies on shared API Management instances that exchange tokens, making it possible to trick the system into using a victim's connection credentials. Despite Microsoft's efforts to add input validation layers, edge cases remain exploitable. The findings were presented at Blue Hat Asia 2026 and highlight systemic weaknesses in Azure Logic Apps' API integration layer.
Source: Hacker News · Summarized by HeadlinesBriefing