Scams

Scams

by Mike Masnick


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craigslist


Inside Craigslist's Increasingly Complicated Battle Against Spammers

from the spam-fight dept

John Nagle writes in with a fascinating dissection of the ongoing battle between Craigslist and spammers. The back and forth nature of this battle is fascinating -- and somewhat disturbing when you realize the lengths to which spammers will go to get spam onto Craigslist, and the extent to which an entire ecosystem of scammers and software providers seems to have been built up around this effort:

"Spam on Craigslist has been a minor nuisance for years. Not any more. This year, the spammers started winning and are taking over Craigslist. Here's how they did it. Craigslist tries to stop spamming by checking for duplicate submissions. They check for excessive posts from a single IP address. They require users to register with a valid E-mail address. They added a CAPTCHA to stop automated posting tools. And users can flag postings they recognize as spam.

Several commercial products are now available to overcome those little obstacles to bulk posting. A tool called CL Auto Posting Tool is one such product. It not only posts to Craigslist automatically, it has built-in strategies to overcome each Craigslist anti-spam mechanism.

Random text is added to each spam message to fool Craigslist's duplicate message detector. IP proxy sites are used to post from a wide range of IP addresses. E-mail addresses for reply are Gmail accounts conveniently created by Jiffy Gmail Creator ("Who Else Wants to Create Unlimited Gmail Accounts in Seconds Flat Without Breaking a Sweat?") An OCR system reads the obscured text in the CAPTCHA. Automatic monitoring detects when a posting has been flagged as spam and reposts it.

CL Auto Poster isn't the only such tool. Other desktop software products are AdBomber and Ad Master. For spammers preferring a service-oriented approach, there's ItsYourPost.

With these power tools, the defenses of Craigslist have been overrun. Some categories on Craigslist have become over 90% spam. The personals sections were the first to go, then the services categories, and more recently, the job postings.

Craigslist is fighting back. Its latest gimmick is phone verification. Posting in some categories now requires a callback phone call, with a password sent to the user either by voice or as an SMS message. Only one account is allowed per phone number. Spammers reacted by using VoIP numbers. Craigslist blocked those. Spammers tried using number-portability services like Grand Central and Tossable Digits. Craigslist blocked those. Spammers tried using their own free ringtone sites to get many users to accept the Craigslist verification call, then type in the password from the voice message. Craigslist hasn't countered that trick yet.

Much of the back and forth battle can be followed in various forums.

It's not clear yet who will win. Craigslist may find something that works. If it doesn't, however, it could be toast for the success story of Craigslist."

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  1. by Jake - May 23rd, 2008 @ 5:42pm

    Hell's bells... I got nuthin'.

    (reply to this comment) (link to this comment)

  2. One solution...

    by Brooks - May 23rd, 2008 @ 6:08pm

    CL should surreptitiously purchase a couple of the companies that sell the spam programs and gather data on their users, then use the data for lawsuits or, perhaps, make it available to some of the more vigilante style CL users. Yes, yes, ethical concerns and all that, but man it must be tempting.

    (reply to this comment) (link to this comment)

  3. by Danny - May 23rd, 2008 @ 6:08pm

    Two things I think fascinating about this.

    1. My gut tells me this is not lots of different spammers gutting CraigsList, but a very small number (maybe one). I have no data to support this gut feeling, but the gut feeling is strong.

    2. These parasites are going to destroy their host. They would get much farther much longer if they figured out some sort of symbiotic relationship.

    (reply to this comment) (link to this comment)

  4. Well

    by Ron - May 23rd, 2008 @ 6:09pm

    We could kill the spammers. They're scum anyways.

    (reply to this comment) (link to this comment)

  5. by Overcast - May 23rd, 2008 @ 6:26pm

    Wonder if the spammers = eBay?

    (reply to this comment) (link to this comment)

  6. by Anonymous Coward - May 23rd, 2008 @ 6:41pm

    Unfortunately, the spammers have won on the personals section.

    Over the last several weeks, I have found about 1% of the posts to be non-spam. Many are obvious. They use the same 'catch phrases', have programming errors that generate obvious errors (field names present instead of actual values, mishandled quotes, age mismatch between title and body, etc.), and mismatched pictures.

    If I can catch most of these obvious spam posts via casual inspection, you would think that a Bayesian filter trained in part by feedback from CL users could do the same.

    I don't know what the ramifications concerning failed posts would be, but it might be better than having sections of the website be completely useless.

    (reply to this comment) (link to this comment)

  7. Re: Well

    by Anonymous Coward - May 23rd, 2008 @ 6:57pm

    Agreed, see a spam notice of any kind track its IP to the registered user and kill them.

    However, this is much less profitable than reporting news about it, lobbying about it, using it as a politcal grandstanding technique, creating software to combat it, creating software to support it, creating analytical firms to help comabt and suport the combative and supportive effort, get a review commity to review how well the analyzers analyze, and then create 100 blogs about all of it with ad space, not to mention all the bandwith and hardware it takes to do all of those.

    Kill some scum or spend millions, in the end what's it really matter when all you've done is be wasteful?

    (reply to this comment) (link to this comment)

  8. Defeating CHAPTCHA is a violation of the DMCA

    by John - May 23rd, 2008 @ 7:08pm

    In a recent case decided in the 9th Circuit the District Court ruled that defeating CHAPTCHA was a violation of both 17 U.S.C. 1201(a) and 17 U.S.C. 1201(b). The Court reasoned that CHAPTCHA "both controls access to protected work because a user cannot proceed to copyright-protected webpages without solving CHAPTCHA, and protects rights, of a copyright owner because, by preventing automated access to the ticket purchase webpage, CHAPTCHA prevents users from copying those pages." Ticketmaster LLC v. RMG Techs., Inc., 507 F.Supp. 2d 1096 at 1111-1112 (C.D. Cal 2007).

    Now I know many of "us" disagree with the DMCA however, it looks to me like Craigslist could use this to prevent the distribution of the software these spammers are using. Maybe, just maybe, in this instance the DMCA could be a good thing.

    -john

    (reply to this comment) (link to this comment)

  9. A fun solution

    by Anonymous Coward - May 23rd, 2008 @ 7:11pm

    Most of these ads are easily identified as bogus. Do what I do, and pretend to be interested in the bogus product, drag it out, waste as much of the scammer/spammers time as possible. Send them mail from bogus accounts, give them phoney telephone numbers, etc.
    If they had to dig through hundreds of people pretending to buy whatever they were trying to sell or scam, they would have to work to figure out who was a real target, vs who was just pretending to be a target.We all know they are too lazy to work, or they wouldn't be trying to rip people off.

    (reply to this comment) (link to this comment)

  10. by Andy`` - May 23rd, 2008 @ 7:21pm

    Did they try using a random simple question system alongside the CAPTCHA? I have no idea whether such a system would be easily bypassable, nor what amount of variation and fresh input would be needed keep up with attempts to get around it, but it could discourage the spammers enough to make them give up, or at least slow down a bit. I've seen it work very effectively on smaller scale sites that have had spam problems, so you never know what upscaling the idea could do.

    However, how effectively any anti-spam measure works probably, in part, depends on the motivations of the spammer...

    (reply to this comment) (link to this comment)

  11. there is a solution

    by Bernard - May 23rd, 2008 @ 7:25pm

    the simple answer is to charge for posting. CL can charge 99c for single posts and that will address the problem. Spam is not a problem limited to an online world. If the post office was to deliver letters without stamps, it will be killed by "Spammers". Besides, 99c will allow CL to beef up their services.

    (reply to this comment) (link to this comment)

  12. spammers

    by Mike B - May 23rd, 2008 @ 8:11pm

    Spammers have completely destroyed the Las Vegas computers section. Up until about 3 months ago it was great, now 1 guy has managed to make it completely useless. Sad thing is that it's been pointed out to CL exactly who this guy is, but they won't do anything apparently cause he just keeps doing it.

    (reply to this comment) (link to this comment)

  13. Re:

    by wasnt me - May 23rd, 2008 @ 8:13pm

    thats was my 1st thought as well.

    although i was reluctant to let the conspiracy theorist in me.

    (reply to this comment) (link to this comment)

  14. Re: Re:

    by wasnt me - May 23rd, 2008 @ 8:17pm

    (oops)

    ... out.

    (reply to this comment) (link to this comment)

  15. Re: Defeating CHAPTCHA is a violation of the DMCA

    by Anonymous Coward - May 23rd, 2008 @ 11:22pm

    The Court reasoned that CHAPTCHA "both controls access to protected work because a user cannot proceed to copyright-protected webpages without solving CHAPTCHA, and protects rights, of a copyright owner because, by preventing automated access to the ticket purchase webpage, CHAPTCHA prevents users from copying those pages."
    CHAPTCHA prevents copying? Now there's a court that really doesn't know what it's talking about. How stupid can they get?

    (reply to this comment) (link to this comment)

  16. Re: Token Charge is the answer

    by Free Market - May 23rd, 2008 @ 11:51pm

    Charging even 1 cent for the posting would be enough. It is the economics of free spamming that make it reasonable for the spammers to keep it up. If we were to charge just 1 penny per posting or email for that matter, the spammers would dry up.

    (reply to this comment) (link to this comment)

  17. CL now needs to charge!!!

    by Paul L - May 24th, 2008 @ 5:21am

    How about 99 cents to post with proceeds benefiting charitable causes in that specific CL market? If it not worth 99 cents for a poster to place the ad, it sure isn't worth my time to read it. Imagine, filtering out all the spam and making CL useful again while benefiting local the local community!

    (reply to this comment) (link to this comment)

  18. by Lucretious - May 24th, 2008 @ 7:31am

    The "Erotic" section is being defended heavily. Thank you Craig!

    BTW, that blackhat site seems to be aware of a rumor thats going around that CL will start charging $5 a pop for sections that require phone verification. I've heard this myself.

    I'm all for it if it decreases spam. I run a weekly ad out of the household services section and would like to see it continue to generate income for me.

    (reply to this comment) (link to this comment)

  19. Re: Token Charge is the answer

    by david - May 24th, 2008 @ 7:42am

    How would you charge just one cent?
    ...use a credit card?
    well, the CC company charges percent of the transaction and a minimum transaction fee!!!
    And, than you have to deal with people who want refunds or error or CC scams and so on...

    (reply to this comment) (link to this comment)

  20. one thing is clear...there will be no clear winner

    by joe - May 24th, 2008 @ 7:54am

    You don't really need to keep score on this one. Where humans are clicking and the postings are free, there will be spammers, and they will automate (they will start by hand but if its profitable, competition will come and then they will need to scale to keep ahead of each other, not so much Craigslist). The commenter who thinks its mostly 1 guy fails to note that there are several products in the marketplace to assist this sort of advertising,not to mention the many talented programmers that make their own systems so they are not caught when CL develops techniques to counter the techniques of the most common applications. CL has worked harder than almost anyone else of size tocounteact spam, but if they succeeded,they'd be the first ones who did.

    (reply to this comment) (link to this comment)

  21. by www.custompcmax.com - May 24th, 2008 @ 7:57am

    These spammers will eventually kill craigslist. When people start to see that everything is spam, they will stop shopping there. It is in the interest of the spammers and craigslist to work out some sort of resolution. Or CL needs to beef up the security even further.

    (reply to this comment) (link to this comment)

  22. by Lucretious - May 24th, 2008 @ 8:38am

    It is in the interest of the spammers and craigslist to work out some sort of resolution.

    what sort of resolution could be worked out? It isn't one connected group. Its thousands of separate individuals looking to get their ads in-in any way possible.

    (reply to this comment) (link to this comment)

  23. Re:

    by Anonymous Coward - May 24th, 2008 @ 8:46am

    "These parasites are going to destroy their host. They would get much farther much longer if they figured out some sort of symbiotic relationship."

    A symbiotic relationship would mean these scammers are clever. They aren't. They're lowlifes who go for the biggest profit with the least possible effort. People with this kind of ethics and IQ (somewhere between the ebola virus and the crackhead who smashed my car window to steal a GPS that wasn't there) aren't able to think long-term.

    (reply to this comment) (link to this comment)

  24. by Jamie Carter - May 24th, 2008 @ 8:51am

    Best way to avoid spam altogether is to read posts and investigate the links yourself ..then decide if it is relevant or not

    (reply to this comment) (link to this comment)

  25. Re:

    by Anonymous Coward - May 24th, 2008 @ 9:13am

    Actually there are many of them. Someone posted a link to a black hat forum, and there were a lot of people making money off of this. They are using the group/open approach to figure out how to bypass all these safety features.

    They are determined that they have every right to destroy CL to make money through spam.

    The real gold here is the email lists these bozos generate.

    (reply to this comment) (link to this comment)

  26. Re: A fun solution

    by Anonymous Coward - May 24th, 2008 @ 9:19am

    AC - these guys are harvesting email addresses, and sending porn spam.

    There is no long drawn out playing with them.

    (reply to this comment) (link to this comment)

  27. Re: there is a solution

    by Chiropetra - May 24th, 2008 @ 10:36am

    Charging a small amount for a service is probably the best answer from an economic standpoint.

    Spam exists because it is essentially free to the spammer. The returns are so low that even a 99 cent charge would make it unprofitable.

    (reply to this comment) (link to this comment)

  28. Pay Ads and Human Verification...

    by Freedom - May 24th, 2008 @ 10:44am

    Seems like the best way to solve this is to do the $0.99 per ad listed and then follow up with human verification of all postings. The $0.99 will provide enough money for human verification services and also ensure that the person listing is serious.

    You could also setup a special verified account holder status and after certain milestones are meet they no longer have to pay and be verified until someones flags their listings as suspect.

    Besides that, best way to stay in front of automated listing agents is to constantly change your verification methods - use different CAPTCHA's, random questions, and keep it as variable as possible. Any system can be broken, but a system that changes every day and is unique for every listing is for all practical purposes a royal PITA for the spammers.

    Another interesting idea would be to setup a wiki like volunteers that would review ads before they are listed and can any that are questionable. Essentially local moderators for high-spam sections, etc.

    Freedom

    (reply to this comment) (link to this comment)

  29. 99 cents per account

    by Paul - May 24th, 2008 @ 11:59am

    Charge 99 cents per account, or 5 dollers per account, just dont charge per post, if your account gets hit with the spam button a few to many times, im sorry, your a spammer.

    Put the rules out ahead of time and you will be fine.

    somethingawful forms costs I think 20 dollers for an account, Thousands of people pay this fee, mods are free to ban accounts and those who get banned are free to make new accounts, making the website more money. Spammers are non-existant on that website (from a readers point of view)

    (reply to this comment) (link to this comment)

  30. by chrism - May 24th, 2008 @ 12:54pm

    gotta love a linkbait article condeming spammers!

    (reply to this comment) (link to this comment)

  31. Re: there is a solution

    by Ramez - May 24th, 2008 @ 7:15pm

    As Bernard said, I think they'll need to charge as well, but I dont think they will be able to charge per post. That would limit the number of new people that use it as well as the long tail of items people post on there. Instead, I think they should charge $1 per email account you register with them and maybe ask you to set up a small profile. That way, spammers would have to pay $1 for every email they try to register and then you could also tie the credit card to a real address and name. As their email addresses continue getting blocked, it will get more expensive for these spammers to keep registering. Maybe even $0.50 is enough to charge.

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  32. by Anonymous Coward - May 24th, 2008 @ 11:07pm

    So, what's going to stop spammers from jacking other people's account information (bank, credit card, etc.) instead and use those for the 99c charge?

    It's back and forth, a never ending battle. You need to strike at the root of the cause, not the symptoms. What's the incentive behind spamming anyway? I can never figure it out. But if you take away the incentive, you'll take away the reason for spammers being there in the first place.

    (reply to this comment) (link to this comment)

  33. Re: one thing is clear...there will be no clear winner

    by Blake - May 25th, 2008 @ 2:05am

    What REALLY gets my 'goat' so to speak, is that they seem to concentrate on single cities.
    I live in Atlanta, and just about
    - every - single - category -
    in the Jobs section is innundated with these pathetic frakking ''work from home___vgthzq4fc6th'' and such like type ads - easy to spot but a pain in de derriere iff'n yer really looking for anything OTHER than a scam - I wish Craigs (this might be a solution) would offer a reward to
    1) sign in as your client ID to the list
    2) track your activity on the List
    3) REWARD you for spotting the spam's!! (30 spotted=free post in a paid section or something like that - hell, there's lots of ways to pay back - and, eventually you'd have the peeps that develop the spamming s'ware developing stuff that SPOTS the spam because they'd get rewarded for it - nice little twist on reality there, hey?)

    I go to a few different cities each day looking for biz, {not posting!!} Replying to posts, and I dont see nearly the amount of spam in any other city - -
    Soo, thats my bee-atch for tonite - SEO rules!

    (reply to this comment) (link to this comment)

  34. Re: Defeating CHAPTCHA is a violation of the DMCA

    by Haywood - May 25th, 2008 @ 7:03am

    Once the genie is out of the bottle...
    DVD-Decrypt is no longer allowed to be distributed, give me 10 minutes and I'll have a copy.

    (reply to this comment) (link to this comment)

  35. It wouldn't make it go a way.....

    by Haywood - May 25th, 2008 @ 7:17am

    But it would slow it down if you had to log on to post. I was surprised when I first posted; that you didn't even need to register to post. The $0.99 per post, or even account idea would work, but it would kill off the free stuff section. CL has grown exponentially because of the open and free nature of it, but that is also its Achilles heel. I do devote as much time as I can to moderating, and so do a lot of others in my area, consequentially, spam isn't all that bad here.

    (reply to this comment) (link to this comment)

  36. uhhh really simple solution

    by Stinkles - May 25th, 2008 @ 9:13am

    just require users to register with a paid email account (your ISP email account)

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  37. by John Smith - May 25th, 2008 @ 9:46am

    No. If software is what they are using to bypass the spam filtering then software can block them permannetly

    (reply to this comment) (link to this comment)

  38. Re: A fun solution

    by Moschops - May 25th, 2008 @ 10:21am

    I agree, there's a time to fight fire with fire - even better do it automatically.

    (reply to this comment) (link to this comment)

  39. Their business model has run it's course, and just use RSS.

    by Steevo - May 25th, 2008 @ 10:40am

    The trouble Craiglist has is that their business model has run it's course. It no longer works. Free ads are being subverted by the spammers and CL now has to adapt.

    Things that are free have no value, and CL likely has insufficient capital to fight fire with fire.

    They need to hire human mods to review all ads before they go live. Expensive. A couple weeks of that and the spammers would go away. But they probably can't do it.

    They could sue the people who are posting the spam, but that might cost too much for their "free" business model.

    There is no good solution for their method of doing business to fight the legions of spammers who are trying to make money by stealing resources from CL and everyone else.

    One thing that makes CL still pretty useful for me is by taking it as an RSS feed. I use Sharpreader to read CL and it picks up my searches and loads them locally.

    One thing this does is it gives you the ad "instantly". You don't have to click the website to see what the heck that is or whether it's the same as the one right below it. It's all there.

    Come to think of it, if CL gave you a brief abstract of each ad right in the category list, enough to tell whether it's spam or not, you wouldn't have to click on the spam to find out what it is and that might make the spam nearly worthless.

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  40. How can you promote a service or product Legally on CL?

    by Phill - May 25th, 2008 @ 1:20pm

    I have been looking for new ways to advertise on the net and was told by a friend that CL was a graet place to advertise because of the high exposure. I've spent several days researching ways to advertise on CL and all I've seen are ways to GAME the system with either software or hiring a firm to post for you like POST2CRAIG or ITSYOURPOST which I'm not even sure are legal and trying to post manually one at a time seems like an effort in futility. This leads me to ask the question is CL a viable way to effectively advertise on the net?

    (reply to this comment) (link to this comment)

  41. agreed

    by katy - May 25th, 2008 @ 6:54pm

    besides the complete anonynmity of craigslist and the associated dangers,I find the spamming to have gotten overly ridiculous. Recently I have come across a website caleed flugpo.com which blows craigs out of the water. I seems safer, its free, and is much cleaner, of both content and spam.

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  42. by Anonymous Coward - May 25th, 2008 @ 7:14pm

    Phill: the people who tell you craigslist is a place to advertise your product or service AT ALL are the spammers and scammers and get-rich-quickers.

    If you're a business selling product or service, PAY FOR ADVERTISING and STAY OFF CRAIGSLIST.

    Thank you, good night.

    (reply to this comment) (link to this comment)

  43. You know what would be funny?

    by Dave - May 26th, 2008 @ 1:52am

    While browsing that lowlife "blackhat" spammer forum you linked to, I suddenly realized that it would be the most hilarious thing in the world if, all of a sudden, somebody decided to build an efficient forum-spamming tool tailored for this site.

    That somebody would definitely be my personal hero.

    (reply to this comment) (link to this comment)

  44. One solution.

    by magoo - May 26th, 2008 @ 10:03am

    Have a human review all submittals before they get posted to the live site.

    (reply to this comment) (link to this comment)

  45. Re:

    by comboman - May 26th, 2008 @ 12:29pm

    So, what's going to stop spammers from jacking other people's account information (bank, credit card, etc.) instead and use those for the 99c charge?

    If I was a criminal with access to someones bank or cc info, I can think of a lot better ways to spend it than funding spam (a different criminal activity with a much lower payout rate).

    (reply to this comment) (link to this comment)

  46. stop it at the source

    by Dutch - May 26th, 2008 @ 1:04pm

    I agree with Brooks, except purchasing the SPAM companies doesn't sound financial feasible. However I do agree that the best way to stop the spam is to attack it at the source. I'm not sure the legality of a SPAM post on a site such as Craigslist but maybe the company can follow Nintendo's suit when they raided the MOD chip creators, I guess that may be difficult unless they can prove they used the anti-SPAM software...

    (reply to this comment) (link to this comment)

  47. by Sigmund Leominster - May 26th, 2008 @ 3:31pm

    Steevo (comment 39) has probably hit the proverbial nail on the head with his comment on the business model based on "free" services. The old adage of "there's no such thing as a free lunch" is still serviceable and when someone claims something is "free," it's worth digging a little to see who benefits - cui bono, as those Romans said.

    With Craig's List, the fundamental issue is that when benefits comes in the shape of a response to a post, the way to increase your chance of getting a response is simply to increase the number of your posts. And if those post take no effort and are free, then the result is clear - spam.

    We all want things free. Some people will spend hours online looking for a crack/hack to a program that costs $30 - and if a few hours of your time is worth MORE than that, you'd be better of paying the cash and doing something more productive! But free can also mean poorer quality, no support, flaky performance, and lots of hassle. Sometimes the "free" solution ends up being expensive.

    And here is where Craig's List sits - a great idea and very very free, but now a victim of its own success to the point of near extinction. Like many "free" enterprises before, the choice is now between closing the doors and charging a fee. I hope the later is preferred.

    (reply to this comment) (link to this comment)

  48. by Jayson - May 26th, 2008 @ 7:47pm

    Charge 5 dollars to open an account. 'Nuff said.

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  49. Re:

    by michael - May 26th, 2008 @ 10:04pm

    I've been impressed with the ASIRRA CAPTCHA here: http://research.microsoft.com/asirra/ Very difficult to hack...

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  50. A Solution

    by Software Engineer - May 26th, 2008 @ 11:37pm

    For those that recommend charging, this would kill CL's business model. However, the need to charge is still valid. To reconcile the two, CL needs to partner with a number of companies (itunes, amazon, paypal, a paid email service, etc). The user then has the option to a) purchase a CL account or b) purchase something from a partner store who will essentially verify to CL that the account is valid. I wouldn't pay to post a small item on CL, but I WOULD buy something from a partner store - that I needed - if that would verify me.

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  51. Safe Websites

    by Rachna - May 27th, 2008 @ 2:27am

    Spaming has to be stopped by some other means. But Charging for the service will not the serve the purpose. It can restrict spams to some extent but it will afect the company's image in the marke. Craigslist is a free online classified and charging will cause complete change in a business policy. Other online classified which provide there service for free include clickindia.com and thisismyindia.com

    (reply to this comment) (link to this comment)

  52. open proxy check

    by Tobias - May 27th, 2008 @ 5:41am

    I've done it with a Movable Type plugin before and CL should do it as well: for each submission, go back to the originating IP and check if you find an open proxy server there. This check is done within seconds and it will weed out a heck of a lot of spam submissions.

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  53. Re: One solution.

    by mkam - May 27th, 2008 @ 5:50am

    Do you have any idea how many posts are submitted to craigslist per minute. Even if a human can make a spam/no spam decision in a couple of seconds, sustainable for a 8 hour work day, you would still need a ton of reviewers. I think it is probably a scaling problem that can't be solved with more people.

    (reply to this comment) (link to this comment)

  54. Theft of Service?

    by Anon C. O'ward - May 27th, 2008 @ 9:58am

    Can someone be charged with 'theft of service' if the service is provided free-of-charge. Providing the service has costs associated with it, which spammers are, in effect, stealing by violating the TOS.
    If they could, would not anyone providing the software that enables the theft be liable for some kind of criminal enterprise charges?

    (reply to this comment) (link to this comment)

  55. Re: Re: A fun solution

    by Einstein - May 27th, 2008 @ 10:06am

    If you use CL you can set up an email that is only used to respond to postings or post merchandise. That is how I get around it. I just empty the mail before I post so I can see if I get any responses.
    Cheers!

    (perhaps only a short term fix but it works for me)

    (reply to this comment) (link to this comment)

  56. Fight fire with fire

    by Anonymous Coward - May 27th, 2008 @ 1:44pm

    Though probably against Craig's "moral compass", I think those blackhat forums would be a lot less useful if, oh, I dunno, one day an onslaught of spam started appearing in them... and their own tactics were used to continue to do so...

    Sometimes the best defense is a good offense.

    (reply to this comment) (link to this comment)

  57. cl

    by screw it all - May 27th, 2008 @ 10:34pm

    everyone who talks about the erotic services section complain about spammers, well all girls post more then one ad on there. The real problem is with craigslist promoting prostitution. Everyone gets mad when they are a legal service and consider it spam, wtf... get mad at the hookers how are spreading stds and setting you up with the cops, not the girls who offer a legal erotic service..

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  58. Better than CAPTCHA

    by David Rowell - May 28th, 2008 @ 7:30am

    Very interesting indeed. I'm amazed that OCR systems can read the distorted letters and numbers that are part of creating a Google email account or apparently Craigslist posting. I find it increasingly hard to do this myself!

    Here's an idea - they should replace the character recognition requirement that is the CAPTCHA process with instead a little question/answer such as 'What is the result if you multiply 2 by two' or 'Enter the third word in this sentence into the verification box', or 'What day of the week is it tomorrow' or anything like that. The possibilities of simple question/answer routines are vast, and if they act as a filter requiring people to have a double digit IQ as well that would be a bonus. :)

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  59. by Robabard - May 28th, 2008 @ 7:40am

    Brilliant! I've thought the same thing.
    eBay is the great enemy of CL.

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  60. Charging and flagging don't mix

    by mellymai - May 28th, 2008 @ 9:30am

    I use Backpage all the time and have no problem whatsoever with paying to post an ad, but I do think it's ridiculous that even Backpage has buttons by which you can flag a PAID post. It's a well known fact that there is not only excessive spam on Craigs and other similar sites, but excessive flagging. If I am a legitimate poster who has paid for my ad, that doesn't mean that someone can't come along and for invalid reasons of competition or just plain trolling flag my ad down. If Craigs starts charging for its posts, too, it needs to eliminate invalid flagging, or trolls will be sitting out there getting the biggest kick out of seeing PAID ads disappear for no reason.

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  61. by SluttyNerdGirl - May 28th, 2008 @ 2:37pm

    I think they should just pay a few of the wankers that read craigslist personal ads anyway to have authority to pull down obvious spam.

    I'm here because my favorite category, Missed Connections, is totally overrun by formulaic ads for fake women looking for dates.

    There must be legal issues involved because these all have photos of women. I'm sure these women didn't give consent to have the spammers use their images.

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  62. by dave - May 29th, 2008 @ 1:24pm

    but who pays the spammers anyway? Seems like those guys are almost worse....

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  63. Stopping spammage

    by Simon Lynch - May 30th, 2008 @ 12:49am

    We've just spent the last 6 months fighting spam on our site. Some lessons: - Human review is quite ineffective, many spam posts are copies of real posts from real people; we have seen human moderation regularly disagree with our spam detection and on a closer look prove wrong. - There are different kinds of spammers, running all the way from script-kiddies running scripts, dudes sat in African Internet Cafés to serious hackers (quite a few coming out of Russia). - Think iterative, don't try and come up with the best system ever. Start, review, improve. We have got to the point where our accuracy is not really quite high, it is possible! For those of you asking about how spammers get paid, see here for some examples (also there are some tips on how to stay safe online): http://classifieds.justlanded.com/en/stay_safe_online

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  64. Re: Stopping spammage

    by Simon Lynch - May 30th, 2008 @ 12:51am

    Doh! "where our accuracy is not really quite high" should read "where our accuracy is really quite high"

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  65. what i don't get is

    by geoff - May 31st, 2008 @ 1:48pm

    why is it when i am looking for a stepvan or whatever i see the same bastard's ad A HUNDRED TIMES (http://sfbay.craigslist.org/search/sss?query=step%20van) and yet when i post just TWO similarly-worded yet very distinct sales ads in two different categories to maximize my search results i get a notice saying that it's "too similar" to another ad. What are these spamers using to have such success? and what kind of fool would pay $4600 for a 30 year old stepvan anyways?

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  66. Anti-Technology

    by Adria Richards - Jun 6th, 2008 @ 8:32am

    I've been on the move away from landlines for years now. It started for me in 2003 with trying out Vonage. The only line I have is my cell phone but I route most of my calls through Skype and now GrandCentral. This is a bad move. There could certainly be something in place to establish the age of Skype accounts as a means to verify that they weren't created just yesterday. How about authentication to a third party tied into OpenID? I agree the spam has increased and someone was actually murdered in Minneapolis here after responding to a Craigslist ad (http://wcco.com/local/katherine.ann.olson.2.461959.html) but blocking VOIP services isn't the solution.

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  67. email lists

    by mb - Jun 13th, 2008 @ 3:25pm

    Are email lists that lucrative? The spam posters in the "motorcycles" section don't respond to emails so they must just want your email address.

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  68. Re:

    by Anonymous Coward - Jun 14th, 2008 @ 9:00am

    stop spamming with your link this website www.custompcmax.com

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  69. CL could prevent some spam by allowing a little more flexibility

    by Mike W - Jun 16th, 2008 @ 12:24pm

    There are some pretty simple things that Craigslist could do to help fight some of the spam.

    One typical type of spam that I see is when someone posts the same ad in numerous geographic locations, which Craigslist prohibits.

    Craigslist should re-think this policy. If someone is selling something that might interest buyers in multiple geographic regions, why not make it so that the poster can post one single ad that can appear in whichever geographic regions the poster chooses?

    Similary, if a poster is selling something that fits more than 1 category, allow the poster to specify up to 3 different categories, such that the one ad appears in all 3. (EBay does this.)

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  70. Re: Re: Defeating CHAPTCHA is a violation of the DMCA

    by jimbo - Jun 21st, 2008 @ 12:24am

    Hey, what do you expect? Court decisions are made by LAWYERS. Enough said.

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  71. Post2Craig services

    by post2craig - Jun 29th, 2008 @ 11:35am

    Lately, Post2Craig.com is getting a bad wrap about it's services. People need to understand that Post2Craig is set up to help the consumer with valuable postings for Craiglist. Post2Craig.com will not and cannot post stupid pyramid schemes or cash gifting programs. ITV Ventures or any kind of marketing techniques that you are selling. Post2Craig.com has the right to post who and what they want. Currently they are helping a lot of consumers post valuable services, and products on Craigslist. If you are interested in posting I urge you to check out www.Post2Craig.com but if you are just looking for someone to bail you out because your service is crap and you cannot post on craigslist anymore do not pay because we do not offer refunds.

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  72. craigslist spam

    by michael bolick - Jun 29th, 2008 @ 1:46pm

    Maybe this is slightly off subject but my problem with spam on craigs list is on the other side. When I post to cl I will get a response(do you still have it) and I reply yes ,almost immediatly I start getting spammed.

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  73. the answer is comprehensive reform

    by SpammersGoAway - Jul 3rd, 2008 @ 11:36pm

    I read every single posting above and have decided that the only solution is a comprehensive approach:

    1.Rotating anti-spam software, because no one version is infallible
    2.Human moderators to both screen ads (for legitimacy only, not content) and to remove obvious violators of policy
    3.Above to be paid by LEGIT advertisers who partner with CL to display their banner ads, special offers, etc.

    Costs for updating steps 1 & 2 would be off-set by revenues from 3. It'd be a wash, and a small price to pay (figurtively speaking) to have our CL back without asking for posters to pay any money out of pocket =)

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  74. Yess.. craigslist is very interesting for spammer

    by miss.smartcute - Jul 8th, 2008 @ 11:18pm

    I agree.. craigslist is one of very popular web application. and million user from US. You know from US only in one month spent million dollar for buying online!

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  75. Re: How can you promote a service or product Legally on CL?

    by rob - Jul 9th, 2008 @ 2:08pm

    Hey Phil, it's unfotunate for you that spammers have created a hostile attitude towards advertising. You know damn well most people hate spam. Craiglist has a "services" section where LOCAL people can advertise their services. Yes, there is a large group of people there, but don't ruin our experience for us. If Craigslist wanted ads, they would charge for them. Or is it that you're just looking for free advertising for which you give nothing back? I don't symapthize with you in that respect, and don't give me that "but, I'm a small business owner" crap. Follow the rules and don't cry when no one wants what you're selling.

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  76. Re: How can you promote a service or product Legally on CL?

    by rob - Jul 9th, 2008 @ 2:08pm

    Hey Phil, it's unfotunate for you that spammers have created a hostile attitude towards advertising. You know damn well most people hate spam. Craiglist has a "services" section where LOCAL people can advertise their services. Yes, there is a large group of people there, but don't ruin our experience for us. If Craigslist wanted ads, they would charge for them. Or is it that you're just looking for free advertising for which you give nothing back? I don't symapthize with you in that respect, and don't give me that "but, I'm a small business owner" crap. Follow the rules and don't cry when no one wants what you're selling.

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  77. Re: Post2Craig services

    by rob - Jul 9th, 2008 @ 2:16pm

    uhm , wait, you're charging money to post in a free ads website? Fuckin jerks! It's supposed to be free!!!!!

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  78. Re: Charging and flagging don't mix

    by Anonymous Coward - Jul 9th, 2008 @ 2:18pm

    good point!!!

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  79. Re: Post2Craig services

    by rob - Jul 9th, 2008 @ 2:24pm

    p.s. your website looks like you spent all of five minutes to put together with your wack template. But I guess credibility doesn't matter to you. After all, you ARE doing selling a service in the grey area. I don't wish you the best of luck on your desperate attempt at a legit business.

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  80. Re: craigslist spam

    by rob - Jul 9th, 2008 @ 2:29pm

    I've had the same thing done to me. next time, edit your ad to say "if the ad is still up, I've still got it" and clearly state to "leave a number"

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  81. Re: the answer is comprehensive reform

    by rob - Jul 9th, 2008 @ 2:41pm

    Hey, I really liked your post. I could deal with banner ads(NO POP UPS THOUGH!!!!!) on craigslist in exchange for better reliability. Craigslist has been a godsend, thanks guys & gals @CL. and thanks to the flagging community!

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  82. We the Spammers of Craigslist

    by John Doe - Jul 10th, 2008 @ 4:02pm

    We are the largest CL posting company, we have approached craigslist on numerous occasions in order to conduct a merger that will allow paid & free postings and a guaranteed way of permanently removing spam however Newmark still thinks that this is his little baby and he refuses to let it grow. Captcha has been bypassed, Phone verification is crap since we are making more money selling verified accounts than anything else what’s next? Voice recognition? Well guess what we have someone working in craigslist so no matter what comes out we will always get past it even if they invent paid postings! For all those that think that we are a scam well maybe the smaller companies like post2craig and ItsYourPost are but I can guarantee you that every ad we post are legitimate ads for jobs or services since we do what no other company does and that’s quality control, we don’t just post any junk for anyone and never will, we wish to preserve craigslist but not with the crap people post we even tried sending links to all the spam posts and scam ads and they repaid us by shutting down our server, well we are back up and with a vengeance, CRAIGSLIST HAS BEEN ASSIMILATED RESISTANCE IS FUTILE!

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  83. Re: spammers

    by Batman - Jul 23rd, 2008 @ 1:17pm

    Tell me who they are and I will go deal withthem personally.

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  84. Spam the Spammers...

    by David - Jul 23rd, 2008 @ 1:20pm

    Let's develop some software to spam the spammers. Over load their mail box's so badly that it make it unprofitable for them to spam.

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  85. by Peugeot-rider - Jul 28th, 2008 @ 2:21am

    I tend to agree that the most effective anti-spam tool is to make listings not free but it also has consequences. Most of what I put on CL is free so now it will cost to give away and couple that with more people reluctant to drive to pickup will probably mean Goodwill or the Salvation Army will be the best solution again.

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  86. C/L and spamm

    by Vince - Aug 2nd, 2008 @ 9:39pm

    Yeah I think C/L gets benefits from spammers
    I try to stop them
    by flagging spamm
    and C/L shut me down !!!..
    C/L told me they were going to BLOCK ME !
    for trying to block spammers,
    And all those illegal non paying job listing
    AND SOMETHING ABOUT TOO many entries on their data base
    I live 30 miles in between 4 different C/L lisiting
    So I know that C/L is in bed with The Spammers for the MONEY !!
    every good paying job SPAMM
    every good freebee SPAMM
    every good anything ( NOT GREAT ) SPAMM
    You flagg and they kick you off !!!!

    ?????? lets see ?????

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  87. anyone know how to design an interactive site similar to craigslist?

    by zachary - Aug 4th, 2008 @ 1:28pm

    I have a concept and need a websie developed. It has nothing to do with craigslist and will not be competition. If anything it may HELP craigslist customers.

    Telecommuting would be ok and while not necessary it would be helpful if you were in the Dallas / Ft worth area.

    Part time to start and as it grows we will need full time web support . . . would you be available then too?

    if this sounds interesting to you or you know someone that might "fit" please email me at zachary@e-scrapsolutions.com

    thanks!

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  88. GRRRRR

    by me - Aug 6th, 2008 @ 7:05pm

    I say we just start tracking down the spammers, going to their houses and cutting off their fucking heads with large hunting knives. It's the only surefire way to make them stop.

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  89. Re: GRRRRR

    by John - Aug 17th, 2008 @ 9:26pm

    That's sounds really bright, Einstein.
    Many of these spammers use trojan horse programs to hijack the computers of innocent people and then use those computer IPs to post spam until the IP is blocked by craigslist.

    Fools like you make these suggestions without even thinking about the consequences. Thank God you're not in charge of policing Cl. You should be ashamed of yourself for even considering such a suggestion.

    (