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YouTube Hit By HTML Injection Vulnerability
Virak writes "Several hours ago, someone found an HTML injection vulnerability in YouTube's comment system, and since then sites such as 4chan have had a field day with popular videos. The bug is triggered by placing a <script> tag at the beginning of a post. The tag itself is escaped, but everything following it is cheerfully placed in the page as is. Blacked out pages with giant red text scrolling across them, shock site redirects, and all sorts of other fun things have been spotted. YouTube has currently blocked such comments from being posted and set the comments section to be hidden by default, and appears to be in the process of removing some of these comments, but the underlying bug does not seem to have been fixed yet."
All of your tubes are belonging to US now.
I went to youtube, but all I saw was crap material. Someone had injected a bunch of crap!
The evolution of this bug exploit was quite interesting to follow up close.
At first it simply prevented any further comments to be posted.
Then text was added.
Then the text was scrolling.
Suddenly, the entire page was blacked out except for the added text.
And that's when the more technical minded people realized much much more was possible.
Bam! Popups!
Infinite popups that lead to browser crashes!
Page redirects to shock sites!
The most sophisticated version I saw actually replaced the Youtube video in-place with the 1man1jar video..
And when the exploit was blocked in the comments, it had a small resurgence as video reply title, before being smacked down once more.
Glorious.
They actually got it fixed a bit after I submitted this story. A shame, lemonparty was a big step up from the usual level of discussion on YouTube videos. More seriously, I'm interested in finding out exactly what happened here. Hopefully Google will post some sort of explanation. YouTube is a massive site and it's somewhat bizarre seeing them make the sort of mistake you'd expect from something put together by a drooling moron with nothing but a "How to learn PHP in 24 hours!" book.
Based on the typical YouTube comment (or video, for that matter), I already hard sort of expected that to be the case.
wait for it... wait for it... And nothing of value was lost!
________
Entranced by anime since late summer 2001 and loving it ^_^
Wow. You'd think somebody would've figured out something like this a long time ago.
Lots of people anonymously "injecting" a bunch of crap into a website for all others to see.
This exploit is just an alternative to the original "Upload Video" button.
A lot of the comments are just troll BS. Most people log on for videos not to read the ramblings of basement dwelling trolls. I try to ignore them but they can be really obnoxious. I don't post on Youtube but I have had things pirated and posted just so they could make obnoxious comments. The work posted was just previs stuff that was just done for editing slugs but it was presented as finished work. It caused some trouble with a client so I got a lot more careful about letting development work out there. It's just sad a handful have to spoil things for everyone else. I used to post a lot of development work on my web site but I stopped completely. Trolls are like the people that talk and answer phone calls and take infants to movies. They really spoil the experience for the rest of us. I say if the comments can't be a constructive outlet then remove them and get rid of that security hole completely. The other option for security would be removing the HTML and go pure text. It's nice having HTML input but you don't really need the formatting for comments and it's always going to be a source of potential holes.
a "How to learn PHP in 24 hours!" book
Does that mean:
1. It teaches you, over the course of an unspecified period of time, how to learn PHP in 24 hours?
2. It teaches you, over the course of 24 hours, how to learn PHP? or
3. After 24 hours have elapsed, it teaches you how to learn PHP?
Note that it doesn't actually teach you PHP. It just teaches you how to learn it.
This isn't a simple mistake, it's a sign of pure incompetence since the developer put no forethought into the uses of the tool he was developing and blindly trusted user input from a textarea. User input is dirty, dirty dirty and any developer who does not clean and sanitize it before consuming it is not doing his/her job.
The summary states that the first script tag was escaped as it should be. It was a bug, not a lack of foresight.
I find it interesting pondering the how and why these things fail-- the insight into how the code must have been put together to fail on a particular input.
My initial guess for this one would be that they escape html and scripts separately-- scripts do not need greater than, less than, and ampersand escaped-- and that detecting the keyword 'script' switched modes from html to script. The fact that the first script tag is properly html-escaped suggests that while it was properly detected, the code to switch between html and script modes did not take this detection into account and switched anyway. I'm going to further guess that this do to some support code meant for the programmers' side inadvertently managed to cross over into user land.
My two cents.
--Dave Romig, Jr.
Get the YouTube Comment Snob addon for Firefox.
YouTube Comment Snob filters out undesirable comments from YouTube comment threads. You can choose to have any of the following rules mark a comment for removal:
* More than # spelling mistakes: The number of mistakes is customizable, and the extension uses Firefox's built-in spell checker.
* All capital letters
* No capital letters
* Doesn't start with a capital letter
* Excessive punctuation (!!!! ????)
* Excessive capitalization
* Profanity
If they didn't redirect ALL videos to a Rick Astley video, they have missed the opportunity of a lifetime.
Slashdot social media options: AIM, ICQ, Yahoo, Jabber and Mobile Text. Why no MySpace?
Comments turned off by default? Great! Any chance they can make that permanent?
YouTube is supposed to be a kid-friendly place. Parents could do their best to try to responsibly monitor and guide their kids' surfing habits, but still fail because of this exploit. This is not funny, nor awesome. This is not someone finding a potential exploit and graciously letting Google know so they can patch it up. Just a bunch of 4channers screwing around, and to hell with the consequences. And people like you encouraging that type of behaviour.
Just because this is The Internet(TM), it doesn't mean that common courtesy need not apply.
From what I've seen, there were not only simple insults and racist annoyances, but numerous redirects to the hardest shock site you've probably ever seen. That video makes 2girls1cup, benzin.avi and even the hardest war-porn look like family-friendly softcore entertainment in comparison. It has something to do with 1 man and 1 jar and I dare you to Google that if you have doubt this is emotionally scarring material.
Physical age doesn't necessarily correspond to mental age. Personally, I've been getting more immature as years pass.
Canada: The US's more awesome sibling.
Indeed, which is why everyone but Perl programmers use library functions rather than writing their own regular expressions for working with markup. As a bonus you avoid little bugs like forgetting to escape '&', and it'll probably escape '"' and ''' as well so you can use it for attributes.
Since this was turned in to a massive, YouTube-wide trolling effort, it's being fixed nearly immediately. What if 4chan hadn't gotten a hold of it though? What if some scammers/spammers did? And used it for weeks? It would have been more subtle, and with YouTube's traffic, it could have been massively successful. Who knows what effect that could have had if this wasn't caught quickly. Did 4chan just do a good thing?
Canada: The US's more awesome sibling.
http://www.xkcd.org/481/
If opportunity came disguised as temptation, one knock would be enough.
3^2 * 67^1 * 977^1
I'm the author, and I uploaded a new version that works with the latest YouTube design a few days ago. It's just pending approval by Mozilla.
Physical age doesn't necessarily correspond to mental age. Personally, I've been getting more immature as years pass.
"I have abandoned the quest for eternal youth and instead setttled for lifelong immaturity"
What I learned from this story:
That goatse.cx is very old news and that there are whole new horrors I never even heard of.
Someone must be looking out for me.
You know you are living a blessed life when you got no idea what 1man1jar or lemon party is. Reminds me of being a little kid and having no idea what the adults were talking about. Only this time I know the value of ignorance.
Let me see. 1 man 1 jar, must be about a man collecting pennies to buy a gift for his mother.
Lemon party? Sweet lemonade for a hot summer day? Sounds fun.
2girls1cup? Two girls riding the magic cup at disney?
Please, don't correct me. Ignorance is bliss.
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.