If that were the case, we'd routinely see mysterious XSS exploits on social networks. The underlying bugs are almost always difficult to target! And yet we do not.
The biggest problem, again, is that the vulnerabilities disappear instantaneously when the vendors learn about them; in fact, they disappear in epsilon time once the vulnerabilities are used, which is not how e.g. a mobile browser drive-by works.
They have a class of attacks which are used for targeted intrusion into foreign entities. Typically espionage or cyberwarfare, so they're not often used (they're aware they might be a one-use attack), but some persist for a long time. Foreign entities also tend not to admit to the attacks when found, so if the vendor is a US entity, often the vendor doesn't find out. We do the same; when our intelligence agencies find out about a US compromise, they often keep mum about it.
I'm not talking about XSS specifically, I mean in general. An XSS isn't usually high-value, but if it affects the right target, it can be very valuable. Imagine an XSS or CSRF vuln in a web interface for firmware for industrial controls used by an enemy state, or a corporation in that state. It might only take 2 or 3 vectors to get to that point and then you have remote control of critical infrastructure.
Oh - and the idea that a vendor will always patch a hole when they find it? Not completely true. I have seen very suspicious things going on at high value vendors (w/their products), and asked questions, and nobody did anything. In my experience, management/devs are often quite willing to ignore potential compromise just to keep focusing on the quarterly goals.
Are these things you think it stands to reason the IC must be doing, or things you know for a fact that they are doing? It stands to reason for a lot of people that the IC must stockpile vulnerabilities, but they don't (they keep just a couple working ones) --- just as an example of counterintuitive things about how CNE works.
It's partly fact, partly reasoning. One fact comes from STUXnet and Snowden Leaks, where they developed and deployed vulns that persisted for years without notice. The other fact is I've interviewed at the research centers and my eyes got pretty wide at the stuff they told me without an NDA, so they're definitely paying a lot to develop and acquire more vulns/new attacks. That was all 20 years ago, but the contracts are still there so there's no reason to suppose it stopped. There's also past NSA directors that've spoken at DEFCON for years about how they want more hackers, and the new cold war with China and Russia has been ongoing for nearly as long.
I'm not saying they stockpile vulns; I'm saying if somebody on the dark web said they had a vuln for sale for $50k, and it could help an agency penetrate China/Iran strategically, it would make no sense to turn it down, when they already pay many times more money to try to develop similar vulns.
You are here implicitly comparing Stuxnet and BULLRUN, two of the most sophisticated and expensive CNE operations ever conducted, with an XSS in Discord.
Why would YOU see a mystery XSS exploit on a social network? The idea of the DoD scoring these little exploits in a box is usually to deploy in a highly controlled and specific manner. You as a layperson is of no interest to them unless you are some kind of intelligence asset or foreign adversary
Wouldn't platforms see the supposed XSS payloads in their logs and publish analyses of them, or at the very least, announce that they happened?
Seems like none of these major websites detected anything, and they are supposed to be top-notch in the world.
It's only because the researcher contacted them.
Also because nobody actively exploited them! You're using the word "detected" to mean "discovered", which nobody working in the field would ever do.
detected: WAF caught or detected the attack and raised an alert, post-exploitation
discovered: they audited or pentested themself and found out, preemptively
I just mean that Coinbase didn’t see anything happening and didn’t take action though the boy successfully exploited the vulnerability on their live system.