2.6
IG2 IG3

Allowlist Authorized Libraries

Asset Type: Applications
Security Function: Protect

Description

Use technical controls to ensure that only authorized software libraries, such as specific .dll, .ocx, .so, etc., files, are allowed to load into a system process. Block unauthorized libraries from loading into a system process. Reassess bi-annually, or more frequently.

Implementation Checklist

1
Assess current protection controls in place
2
Configure and deploy required security controls
3
Test control effectiveness in non-production environment
4
Deploy to production and verify functionality
5
Document configuration and operational procedures
6
Draft policy/procedure document
7
Obtain stakeholder review and approval
8
Communicate to affected personnel
9
Schedule periodic review and updates
10
Establish software authorization review process
11
Deploy application allowlisting technology
12
Maintain and update authorized software list

Threats & Vulnerabilities (CIS RAM)

Threat Scenarios

DLL Hijacking and Side-Loading Attacks

Integrity

Attackers place malicious DLLs in application directories or system paths to be loaded by legitimate processes, achieving code execution within trusted process contexts.

Supply Chain Library Poisoning

Confidentiality

Compromised shared libraries from third-party vendors or open-source repositories are loaded into system processes, providing attackers with code execution through trusted channels.

Vulnerabilities (When Safeguard Absent)

No Restriction on Library Loading

Without library allowlisting, any DLL, SO, or OCX file can be loaded into a system process, allowing attackers to inject malicious code through library manipulation.

Unvalidated Shared Library Integrity

The absence of controls verifying library authenticity before loading means modified or replaced libraries execute with the same privileges as the host process.

Evidence Requirements

Type Evidence Item Collection Frequency
Technical Configuration screenshots or exports showing protection controls enabled Captured quarterly
Document Procedure documentation for protection measures Reviewed annually
Document Governing policy document (current, approved, communicated) Reviewed annually