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 document is making an essentially syntactic modification to an existing specification so that the suite of specifications applies a uniform approach to extension syntax.

As such, the proposal does not raise new security concerns beyond the normal concerns raised by syntax.

One concern that is raised is the risk of attack through construction of an attribute with a Tag-Length-Value such that the specified length is invalid being either negative (in signed arithmetic) or greater than the size of the enclosing construct.

While both concerns can be avoided through appropriate coding techniques, a note to remind implementers that caution is required is appropriate.