>I could see a e.g. XSS worm being useful for spreading an advertisement from status to status, but there are two issues with that hypothesis: 1) Facebook is centralized, so the flaw would have maybe 24 - 48 hours of utility and 2) it's not even necessary to use a vulnerability to spread bullshit on Facebook newsfeeds, so why pay for it?

Someone paid 100k to put an exploit pack on redtube for a couple of hours, I'm sure they'd pay much more for a XSS worm allowing them to do the same on facebook. The average value per install in western countries with cryptolockers and FakeAV is really high.

>The alternative claim is that someone would pay a lot of money for a security vulnerability compromising a high value account belonging to a celebrity, journalist, politician, etc. I still find this difficult to believe, because there doesn't appear to be a historical precedent for it. Most such attacks focus on brute-forcing a password or other authentication mechanism.

I don't know, I used to regularly get requests from entertainment industry businesses asking me to compromise competitors facebook accounts for obscene amounts of money. Same goes for jealous ex boyfriends, even though the sums offered by them only tended to be a couple of grand.

While certainly true for a plenty of other sites, the claim that there's no market for FB bugs simply has zero basis in reality.