Subject: Roman Danyliw's No Objection on draft-ietf-httpbis-cache-16: (with COMMENT)

From: Roman Danyliw via Datatracker <[email-masked]>
Date: Thu, 10 Jun 2021 05:30:35 -0700

Roman Danyliw has entered the following ballot position for
draft-ietf-httpbis-cache-16: No Objection

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COMMENT:
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Thanks to Derek Atkins for the SECDIR review.

** Section 7.  It would be worth mentioning that user-agents that have
interactive human users such as browsers should provide a means to explicitly
purge the contents local cache.

** Section 7.  Per “Caches expose additional potential vulnerabilities, since
the contents of the cache represent an attractive target for malicious
exploitation”, do you mean “expose an additional attack surface” (rather than
“potential vulnerability”)?

** Section 7.1.  Per “Various attacks might be amplified by being stored in a
cache”, this text is vague.  Is there a specific amplification tied to given
attack being suggested here, or is this meant to suggest that the presence of a
malicious payload in a cache seeded by an attacker could reach multiple users?

** Section 7.2.  Recommend being clearer on the threat rather than the attack
vector (“timing attack”):

OLD
This is sometimes called "double keying."

NEW
This is sometimes called "double keying” and provides isolation between
cross-origin content.