Insufficient Granularity of Access Control
The system implements access controls intended to restrict access to sensitive hardware resources, peripherals, registers, or memory regions. However, the access control policy is too broad and does not provide sufficient granularity between different agents, privilege levels, address regions, or operation types such as read and write. As a result, an unauthorized or lower-privileged component may gain access to assets that should be restricted, including security-sensitive configuration, interrupt controllers, memory regions, or key material.
This weakness can allow untrusted agents to read protected data, modify device configuration, bypass intended privilege separation, or manipulate system behavior. In hardware and embedded environments, overly broad access control can be especially dangerous because the policy may be enforced at a low level and relied upon by firmware, operating systems, or trusted components as a security boundary.
Remediation
Implement more granular access control policies that separate permissions by agent, privilege level, resource, address range, and operation type. Read and write permissions should be controlled independently, and distinct peripherals or memory regions should not share access control entries unless they genuinely require identical security treatment. Review the access control design during architecture, implementation, and testing, and verify the policy through pre-silicon, post-silicon, and system-level security tests.
Metadata
- Severity: critical
- Slug: insufficient-granularity-of-access-control
CWEs
- 1220: Insufficient Granularity of Access Control
OWASP
- A01:2021: Broken Access Control