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The Real Reason Why AT&T Blocked 4Chan

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SafariScreenSnapz017AT&T (s t) has finally issued a statement about the company’s unannounced blocking of certain parts of forum site 4Chan. A number of parties blamed AT&T for “censoring” the Internet, presuming that the company had blocked access because of the content on 4Chan, which can range from classless to tasteless to everything in between. In fact, AT&T said it blocked one section of the site to control a distributed-denial-of-service attack that was affecting an unnamed AT&T customer. 4Chan is, for lack of a better term, the “Wild West” of the Internet. It is an unedited, unmoderated message board that is surprisingly influential on the Net. 4Chan users have been credited with starting lolcats and RickRolling. Last year, a 4Chan user allegedly hacked into Sarah Palin’s Yahoo Mail account and posted the password on 4Chan. The site, especially its /b/ page, is an interesting place — very, very “not safe for work.”

According to a statement from the phone giant:

Beginning Friday, an AT&T customer was impacted by a denial-of-service attack stemming from IP addresses connected to To prevent this attack from disrupting service for the impacted AT&T customer, and to prevent the attack from spreading to impact our other customers, AT&T temporarily blocked access to the IP addresses in question for our customers.  This action was in no way related to the content at; our focus was on protecting our customers from malicious traffic.

Overnight Sunday, after we determined the denial-of-service threat no longer existed, AT&T removed the block on the IP addresses in question. We will continue to monitor for denial-of-service activity and any malicious traffic to protect our customers.

The story got legs on Reddit, where many commentators scorched AT&T, saying the company “censors the Internet,” and 4Chan fans formed bulletin boards to organize “retaliation” against AT&T. TechCrunch wrote that blocking a web site without notification is an “extreme breach of user trust.” Of course, the blocking evidently wasn’t over 4Chan’s content, which AT&T assures me it would never do, but instead over network protocols that were affecting other customers.

Net neutrality is all well and good, but when one particular server is negatively impacting other users, AT&T is obligated to respond. Not everyone jumped on the blame AT&T bandwagon, however. Late last night, Shon Elliott from unWired Broadband wrote on the North American Network Operators Group mailing list:

There have been a lot of customers on our network who were complaining about ACK scan reports coming from We had no choice but to block that single IP until the attacks let up. It was a decision I made with the gentleman that owns the colo facility currently hosts 4chan [sic]. There was no other way around it. I’m sure AT&T is probably blocking it for the same reason. 4chan has been under attack for over 3 weeks, the attacks filling up an entire GigE. If you want to blame anyone, blame the script kiddies who pull this kind of stunt.

20 Responses to “The Real Reason Why AT&T Blocked 4Chan”

  1. kjzxbfd

    Packet sources can be spoofed. The result of a DDoS can look as though it’s coming from a single source, much like it could seem with a proxy. This story is less about 4chan and more about communication between network admins. Harmful traffic can come from anywhere. It has and will exist no matter if this single forum is there or not.

  2. Wow, you guys are some real losers. Seriously AT&T did the right thing. It is their job to protect their customers and their network. They have no obligation to contact 4chan. Those of you that defend 4chan are some of the biggest losers in the world. Do you realize 4chan is WORSE than the dungeon and Dragon losers of the 80’s?

  3. And once again, it NEVER fails with the incessant lying, as lying is a way of life for these hacker creeps. I salute AT&T for blocking viruses, trojans and nasty spider scripts, as that is what the REAL truth is as to WHY AT&T has flashed the middle finger [blocked] to 4 Chan. Why should AT&T waste time and energy in dealing with viruses, trojans and uncontrollable script programs emanating from the 4 Chan site?

    I don’t condone censorship and I certainly don’t condone lies “in the name of lulz”. The only thing 4 Chan has proven again and again, is that they are infantile and violent. A bunch of two year olds who go on tirades. And just like an out of control two year old, they need some REAL hard slaps from the school of hard knocks.

    Any consequences or denial of internet access to AT&T customers due to NAZI actions emanating from 4 Chan [or any other hacker creeps for that matter], I pray that they are caught, rounded up, prosecuted beyond the extent of the law, thrown in a windowless cell and locked up forever until the day they die.

    I commend AT&T for taking the step forward and I sincerely hope that other ISP’S follow suit ASAP. ENOUGH IS ENOUGH. Hackers cause destruction, chaos, waste everyones time and energy. Normal people on the net are SICK AND TIRED of these two year old tantrum antics that 4 Chan displays on a daily basis. These hacker creeps really and truly need to GROW THE F*** UP.

  4. Why are geeks who are supposed to be in favor of free use of the Web whining about a shutdown of a DDOS source. Is the script kiddy a cousin or what?

    Cripes! Grow up.

    Sorry, that’s already been suggested.

    • Why are you assuming the source of the DDOS (AT&T is talking about a DOS, not a DDOS by the way) was 4chan?

      You do know that packets can be spoofed?

  5. A single AT&T customer, as the press-release states, is affected by a denial of service attack from what appears to be 4chan and AT&T effectively blackholes that IP without contacting 4chan? Apart from that, AT&T pretty much points the finger at 4chan with this press release.

    I’m sure a company the size of AT&T has better ways of dealing with denial of service attacks coming from a single IP…

  6. Daniel Golding

    Mr. Anonymous,

    You need to take it easy and relax. Seriously.

    In the immortal words of Shatner:

    “You, you must be almost 30… have you ever kissed a girl?

    I didn’t think so! There’s a whole world out there! When I was your age, I didn’t watch television! I LIVED! So… move out of your parent’s basements! And get your own apartments and GROW THE HELL UP! I mean, it’s just a TV show dammit, IT’S JUST A TV SHOW! ”

    That applies so well to 4chan.

  7. Anonymous

    Where’s your source on that? Show us an AT&T hosted page with an official response else you are just another pix or it didn’t happen blogger. They are now trying to avoid the shitstorm that is sure to follow from their folly.