How do you prove the SQL injection vector exists unless you take over someone's site?
etc., etc.
This was far from a harmless proof-of-concept app, and "I just wanted to prove I could" isn't sufficient justification for it.
We don't know what his level of communication was with Apple, but it doesn't appear that he notified them before testing this exploit. Had they refused to address the issue or otherwise brushed him off, this would be a reasonable escalation. The same story on r/netsec [1] is being linked to a Forbes article [2], which claims he notified Apple three weeks ago. That's not a ton of time.
Ultimately, he very much violated their ToS and Apple is well within their rights to give him the boot. Whether that was a smart decision on their part remains to be seen.
[1] http://www.reddit.com/r/netsec/comments/m48gx/charlie_miller... , http://www.reddit.com/r/netsec/comments/m3uwo/mac_hacker_cha...
[2] http://www.forbes.com/sites/andygreenberg/2011/11/07/apple-e...
> .. otherwise this was a mute point.
"moot". Pretty please, the word is "moot."Otherwise, while I think you've got a point (he could have used pricing to ensure no one ran his app), that isn't the issue here. The disclosure is. No one is contending he did something evil with his code, it's that Apple is mad about his code and disclosure. I don't think making it unlikely to be purchased would have helped.
It indicates both a security flaw in the platform itself, and a security flaw in the app store approval process, both should be highlighted.
[1] Or perhaps someone beat him to it: he may not have seen the acceptance mail before someone already noticed the app? I'm not familiar with the exact process: do you need to give final approval or can the app be in the store for a while without you knowing it?