AWS to Quick admins: The access control didn't work, but you weren't using it anyway, so what's the problem?

Most users put up with AWS the way you put up with the DMV. I say this with love, but it's hard to disagree that the UI is awful. The console is a UX time capsule if time capsules weren't allowed to ever look like other time capsules. The pricing pages were designed by someone who hates you personally, and you accept all of it because the one thing AWS has historically gotten right is the boring, important stuff. The security model. The IAM language no one likes, but everyone trusts. The boundary between your account and someone else's. Get that wrong, and the whole bargain collapses. So when Fog Security disclosed an authorization bypass in Amazon Quick on May 12 (that's the BI service formerly known as QuickSight, briefly known as Quick Suite, and now apparently just Quick, but check back next week) and AWS responded with a statement claiming "no customer data was at risk," it's fair to ask which definition of customer data they're using. Because it isn't an obvious one, and it certainly isn't mine. What Fog found Fog reports that when an Amazon Quick administrator (which is an absolutely devastating personal insult) uses "custom permissions" to explicitly deny access to AI Chat Agents, the UI correctly hides the feature. Great! Awesome! I sure wish to hell I could do that with S3 buckets to which I do not have access! Notably, there's no other way for an admin to do this - it's custom permissions or naught. The API, however, was perfectly willing to keep answering chat requests for any user in the account who knew how to send them. Fog's proof-of-concept was a non-admin asking the agent "Tell me about mangoes" from a session that was, on paper, locked out of the agent entirely. The agent told them about mangoes. AWS deployed the fix between March 11 and March 12, eight days after Fog reported it via HackerOne. So far, so coordinated. Seriously, for a company of this scale, that's underpants-outside-the-pants superhero speed. Good for you; gold star. What came next Where this gets uncomfortable is the response. AWS classified the severity as "none." It issued no customer notification. It published no advisory. After Fog disclosed the HackerOne report and published a blog post, AWS provided a statement to Fog Security reading, in full: "We appreciate Fog Security's coordinated disclosure. This issue was addressed in March 2026. No customer data was at risk and there is no customer action required. As always, customers can contact AWS Support with any questions or concerns about the security of their account." Take that sentence apart and see how much work "no customer data was at risk" is doing. Amazon Quick is described on its own product page as an AI assistant that "connects Slack, Microsoft Teams and Outlook, CRMs, databases, and documents in one place" and "grounds every answer in your real business data." The default chat agent, which is automatically and annoyingly provisioned the instant Quick is enabled whether the customer wants those AI features or not, is the front end for that data. It is the whole point of the front end for that data. Now consider the actual scenario AWS just patched. An administrator at, say, a regulated bank (an unregulated bank is called "a criminal enterprise that hasn't been caught yet") configures custom permissions denying chat agent access to a large group of users. Maybe those users are contractors. Maybe they're in a business unit that isn't cleared for AI tools. Maybe the bank's compliance posture flat-out prohibits shadow AI usage on top of internal data. Until two months ago, every one of those users could send an HTTP request directly to the agent endpoint and get a response. Fog asked about mangoes because they're a security firm doing a clean disclosure, not a malicious insider. A malicious insider would not have asked about mangoes. The question to AWS, with no rhetoric attached: In what sense was customer data not at risk? Either the chat agent doesn't actually have access to the data the product page says it does (in which case the marketing department has some serious splainin' to do) or unauthorized users could query an agent wired into customer data, in which case "customer data was at risk" is the correct English-language description of the situation. AWS clarifies, and says the quiet part out loud After this story started circulating, AWS offered a follow-up comment that I sincerely appreciate, because it's so much more honest than the first one. Per a hounded-looking AWS spokesperson: "The researcher was using the Admin Control capability that no customers were actively using when the server side validation was not present." Reading that twice doesn't help. Let me translate. AWS is saying: Yes, the server-side authorization check was missing. Yes, an authenticated user in your Quick account could bypass the only access control mechanism the service offers. The reason this is fine, apparently, is that no real customer had bothered to configure that access control during the window when it didn't work. Um ... what? The defense isn't "the bug wasn't real," which you could be forgiven for hearing in AWS's first statement. The defense also isn't "the bug couldn't have done what Fog says it could have done," which is the even stronger implication of their first statement. The defense is "the access control didn't enforce what we said it did, but luckily nobody was relying on it." This is the corporate-comms equivalent of "the lock on the front door didn't work, but nobody had locked it anyway, so why are you upset?" It's also a surprisingly specific telemetry claim. AWS is asserting that they know zero customers had configured custom permissions to deny chat agent access during the exposure window. That's a confident thing to say, and an even more interesting thing to volunteer as a defense, because it doubles as a withering review of Quick's access management model: the only knob the service provides for this purpose, the one AWS's own documentation explicitly tells administrators to use, has zero recorded uptake. The same follow-up also pointed back to the HackerOne thread to demonstrate that AWS told Fog throughout the disclosure window that "user-based authorization remained enforced." Translation: you needed authenticated credentials in the same Quick account to exploit this. Yes. That's intra-account scope, which Fog documented in their writeup, and which is precisely the scope in which custom permissions are supposed to function as a security boundary. AWS saying "user-based authorization was fine" is saying "you couldn't exploit this anonymously from the internet," which was never the threat model in question. The threat model is the contractor with valid SSO credentials whose admin tried to lock them out of some datasets. Why this matters more than it sounds Amazon Quick's access model is already an outlier: IAM policies don't govern Quick's AI Chat Agent, SCPs don't apply, and RCPs don't apply. Custom permissions are the only knob the service provides. If those don't enforce, nothing else does. And per AWS's own follow-up, literally nobody was using them anyway. Both halves of that sentence should be alarming, and AWS is offering them as reassurance. AWS's competitive moat for the last decade hasn't been pricing. It sure as poop hasn't been developer experience, documentation, console design, or the inscrutable poetry of service names. It's been the well-earned belief that AWS gets the foundational things right: boundaries, identity, durability, reliability, and the parts customers can't easily verify themselves. Customers have paid the AWS premium because they trusted the boring stuff. This year that trust is being tested in a way it hasn't been before. The 2025-2026 cadence of AWS security advisories has noticeably increased, for reasons that are as yet unclear. Coordinated disclosures from independent researchers keep surfacing missing authorization checks in newer, AI-adjacent services. The fixes are landing fast, which is good. The customer communication isn't landing at all, which is, charitably, a choice. A "severity: none" rating on a bypass of the only access control a service offers is not an objective security finding so much as it is a communication decision. And the communication decision now reads, with the benefit of AWS's follow-up: "We'll fix the bug, we won't tell you it existed, and if you ask we'll explain that you weren't using the feature anyway." AWS gets a lot of forgiveness on the small stuff because they own the big stuff. They might want to reconsider how much of the big stuff they keep classifying as "none." (R)