Executive brief
Microsoft Azure CycleCloud, a tool used for managing High Performance Computing (HPC) environments, contains a security flaw that allows an existing user to gain higher levels of permission than they should have. By exploiting this lack of proper authorization checks, an attacker who already has basic access to the network can modify system settings or perform actions reserved for administrators. This could lead to unauthorized changes in the computing environment and potential disruption of operations.
Technical details
A missing authorization vulnerability (CWE-862) exists in Microsoft Azure CycleCloud versions prior to 8.9.1. The flaw allows a remote attacker with low-privileged user credentials to bypass authorization checks over the network. By exploiting this root cause, the attacker can achieve an elevation of privilege, specifically impacting the integrity of the system (CVSS I:H). The attack does not require user interaction or high complexity. Microsoft has addressed this issue in Azure CycleCloud version 8.9.1.
Affected products
- Microsoft Azure CycleCloud >= 1.0.0, < 8.9.1
Timeline
- 2026-07-14: disclosed
- 2026-07-14: advisory