I have reviewed this document as part of the security directorate's ongoing effort to review all IETF documents being processed by the IESG. These comments were written primarily for the benefit of the security area directors. Document editors and WG chairs should treat these comments just like any other last call comments. The summary of the review is Ready with issues. This document defines a YANG data model for ACL. When the term "ACL" is used in this document it means the sort of ACL that you might see in firewall rules (e.g., "drop IPv4 traffic with destination port 21"). *Overall Clarity and Quality* The document is fairly clear and well written. However, there is a confusing typo that is listed in the Minor Errors section of this review. *Security Analysis* The Security Considerations section is brief but decent. However, the last two sentences are unclear and maybe wrong: Unauthorized write access to this list can allow intruders to access and control the system. Unauthorized read access to this list can allow intruders to spoof packets with authorized addresses thereby compromising the system. Which "system" is referred to here? Whatever the answer to that question, I believe that the main impact of unauthorized write access to the ACL is that the attacker can modify the ACL to permit traffic that should not be permitted or deny traffic that should be permitted. The former may result in denial of service or compromise of systems on the network. The latter may result in denial of service. The main impact of unauthorized read access to the ACL is that the attacker can determine what ACL rules are in effect and may be able to use this information to better craft an attack. *Minor Errors* Section 3 refers to "action criteria". Every other part of the specification refers only to "action" or "actions". My review of the specification indicates that this text in section 3 should say "actions" not "action criteria".