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id: "CM-07(05)" title: "Authorized Software — Allow-by-exception" family: "CM" family_name: "Configuration Management" sort_id: "cm-07.05" priority: "P1" implementation_level: "system" parent: "CM-07" enhancement: True

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Identify {{ insert: param, cm-07.05_odp.01 }};

Employ a deny-all, permit-by-exception policy to allow the execution of authorized software programs on the system; and

Review and update the list of authorized software programs {{ insert: param, cm-07.05_odp.02 }}.

Guidance

Authorized software programs can be limited to specific versions or from a specific source. To facilitate a comprehensive authorized software process and increase the strength of protection for attacks that bypass application level authorized software, software programs may be decomposed into and monitored at different levels of detail. These levels include applications, application programming interfaces, application modules, scripts, system processes, system services, kernel functions, registries, drivers, and dynamic link libraries. The concept of permitting the execution of authorized software may also be applied to user actions, system ports and protocols, IP addresses/ranges, websites, and MAC addresses. Organizations consider verifying the integrity of authorized software programs using digital signatures, cryptographic checksums, or hash functions. Verification of authorized software can occur either prior to execution or at system startup. The identification of authorized URLs for websites is addressed in CA-3(5) and SC-7.

Assessment Objective: {{ insert: param, cm-07.05_odp.01 }} are identified;

Assessment Objective: a deny-all, permit-by-exception policy to allow the execution of authorized software programs on the system is employed;

Assessment Objective: the list of authorized software programs is reviewed and updated {{ insert: param, cm-07.05_odp.02 }}.

Configuration management policy

procedures addressing least functionality in the system

configuration management plan

system design documentation

system configuration settings and associated documentation

list of software programs authorized to execute on the system

system component inventory

common secure configuration checklists

review and update records associated with list of authorized software programs

change control records

system audit records

system security plan

other relevant documents or records

Organizational personnel with responsibilities for identifying software authorized to execute on the system

organizational personnel with information security responsibilities

system/network administrators

Organizational process for identifying, reviewing, and updating programs authorized to execute on the system

organizational process for implementing authorized software policy

mechanisms supporting and/or implementing authorized software policy