Ask HN: Massive vulnerability on Twitter?

https://news.ycombinator.com/item?id=1334735

by hcho • 16 years ago

57 48 16 years ago

news.ycombinator.com

It seems that you can make anybody follow you by tweeting "accept username". Does it work for you too? This looks like an awful vulnerability to me.

wherespaul• 16 years ago

http://twitter.com/conanobrien yep it is working. Conan is following 23 people now. He only follows one person.

alexro• 16 years ago

The number of conanobrien's "friends" is going up ...

jasonrojas• 16 years ago

I am one of them! Definitely strange how twitter would allow these "commands"...

codesink• 16 years ago

If that works there must be other "cool" commands the coder added after implementing this one...

tszming2• 16 years ago

Confirmed and it works, nice catch.

How do you find it?

trickjarrett• 16 years ago

I believe the 'Accept' is used when you are in private mode and you get notice that someone wants to follow you. So they don't check if the user is in the request queue. Bad bad programmer.

angilly2• 16 years ago

conan is following me too.

wow.

tszming2• 16 years ago

obama is following me :)

angilly2• 16 years ago

... ditto. :)

mortenjorck2• 16 years ago

It's not just a false display, either; it's a real follow: I tried it against my main account using a secondary account, posted a tweet, and then checked Twitterrific on my main account. The new tweet was right there at the top.

nkm2• 16 years ago

It works through the mobile web too

shareme• 16 years ago

confirmed it works

sgtpepper• 16 years ago

What about "reject"? Can you get people to UNFOLLOW you as well?

fname2• 16 years ago

you might, but not using reject.

bena2• 16 years ago

Yeah, block them, then they won't be able to follow you. Although if your timeline is not private they can still read your feed at twitter.com/yourname

TotlolRon• 16 years ago

Massive oil spill on the social graph. Cleaning would be just as fun.

cyanbane• 16 years ago

Perfect analogy. Looks like Twitter is resetting followers/followees as we speak for people trying it. Is this their 4 story containment unit?

hcho3• 16 years ago

Good lord, how would twitter recover from that? Possibly by undoing follow's between the moment this bug has surfaced and the moment they suspend following. Meanwhile they'll loose a huge number of legitimate follow request. Terrible stuff.

igorgue• 16 years ago

LOL... sorry but when you say it that way it's actually pretty funny.

nkm2• 16 years ago

I suppose they have a record of all the commands executed.

hcho3• 16 years ago

Follower and followee counts seem to be back. Anyone seeing lost legitimate follows?

bena2• 16 years ago

Or find all statuses that have the pattern of "accept <valid_username>" and then removing <poster> from the <valid_username>'s followers.

That's not the hard part.

The hard part is that it seems that twitter wasn't checking accept messages to see if they were actually requests behind them or if the accepting user is actually a restricted account. So now they have to implement a mechanism that associates follow requests with follow acceptance.

Currently, the exchange is probably something like this behind the scenes: me: @restrictedUserIWantToFollow lemme follow you them: accept guyWhoWantsToFollowMe Everything simply implemented as twitter messages to facilitate cell phone usage. However, the accept message just assumes that there is a valid request being made and adds them to your followers.

Assumption: the mother of all foul-ups.

jaxn• 16 years ago

2nd Assumption: Twitter stores commands that don't get posted as statuses.

icey4• 16 years ago

It looks like this guy is the one who discovered it:

http://twitter.com/borakrc

hcho3• 16 years ago

and his account has been suspended.

mortenjorck2• 16 years ago

Sorry, the profile you are trying to view has been suspended.

icey4• 16 years ago

Wow, that was quick (or the timing was just right) - it was available 10 minutes ago.

nayanga• 16 years ago

http://webcache.googleusercontent.com/search?q=cache:LbbZ1HN...

dualboot• 16 years ago

Fail. Whale.

JakaJancar• 16 years ago

Good thing they have OAuth.

balu2• 16 years ago

That's quite funny. I just wanted to try this out and received an internal server error. Now all my followers are gone nor am I still following anyone. Twitter strikes back!

benatkin• 16 years ago

It's 0 for me, and I didn't send an "accept" tweet.

balu2• 16 years ago

Funny though ;-) Those guys are quick!

th0ma5• 16 years ago

looks like they are getting on top of it, it is on mashable, and i now have 0 followers and am following 0. nice fun, best pr would be to clean it up, and publish who did what and when (hahah)

icey4• 16 years ago

Kudos to Twitter for taking action quickly at least.

bittersweet• 16 years ago

It seems they are doing something about it already, the few 'high profile' users I checked now have 0 following and followers.

endlessvoid94• 16 years ago

Seems to be fixed. I get an internal server error now. Damn, that was interesting.

fname2• 16 years ago

Looks like they're working on it... following/followers counts are blank for everyone

faramarz2• 16 years ago

DO NOT DO IT! I just attempted an Accept BillGates and both my "followers" and "following" are reset to zero. this better be a bug. http://twitter.com/faramarzhashemi

uptown• 16 years ago

Actually, I didn't do it .... and everything is set to 0's on my profile as well. Either it's part of their clean-up, or their attempts to fix this accidentally wiped everybody back to zero.

faramarz2• 16 years ago

Yea.. Sorry folks. Pre-mature panic. Looks like a site-wide event

robinduckett• 16 years ago

Stephen Fry is following me XD

jffortier• 16 years ago

Just lost all my followers and the people i was following!!!! OMG!!!! Twitter took action.

jashmenn• 16 years ago

Looks like they are fixing the problem, everyone has 0 followers and 0 following right now.

icey4• 16 years ago

All twitter accounts are reporting 0 followers / 0 following. This is going to be a fascinating study on how Twitter manages crises.

rondobley• 16 years ago

yep me too, 0 and 0 after testing it . . .

kevinp• 16 years ago

Ah, the joys of in-band signaling. Now, where'd I put my blue box?

Ask HN: Massive vulnerability on Twitter?

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