Why wouldn't it be considered a bug that accessing one low-permission S3 bucket allowed him to access all the other buckets, including user data and keys?
Both tptacek here and Facebook claim that he found one bug. He found at least two, depending on how you classify things: even if Facebook would not like to admit that their security architecture around token amanagement was/is deficient, and the fuzziness of internal security boundaries makes "bug" somewhat hard to define, it was deficient by industry standards (especially for such a large and tech-focused company), and he got way more access than that RCE should have given him. Whether or not he was supposed to go looking for such additional bug(s), it's discourteous not to at least acknowledge that he found them, and thereby provided Facebook additional value over just finding the RCE.
If he had told Facebook that at the same time as he reported the credentials he harvested from the database --- which his timeline suggests he could have --- I'd agree with you.
But he didn't. He put the credentials in his back pocket so he could pull them out when they suggested he hadn't found his "million dollar bug". And so for a month after they fixed the bug, some fucking rando is walking around with credentials to all of Instagram's AWS assets, totally unbeknownst to anyone at Facebook. They turn down his bid for his "million dollars", and he busts the credentials out on them. You think they're going to thank him?
He's lucky it was Stamos and not Mary Ann Davidson.
I think the point is that, after the first bug report those credentials SHOULD NOT WORK because their job should have included revoking ANYTHING that system have access to. How did they know Wes was the first person to find that bug and the linked credentials?
So, the fact that those credentials still worked a month later is a HUGE FUCKING DEAL! Alex, the consummate professional, didn't do his job and instead had a knee jerk reaction to someone slapping that fact in his face.
It has been incredibly interesting reading through those threads. People are arguing two completely different arguments. tptacek is saying that the dude keeping AWS keys without disclosing this was bad and guy is lucky to not get a early morning wake-up call from men with guns. slewis, comex et al are saying that Facebook not locking down and later disabling AWS keys was bad and Facebook was lucky they didn't get sold on black market. Both sides are correct but it's informative who makes which arguments.
