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Have Spammers Overcome the CAPTCHA?
thefickler writes "It appears that spammers have found a way to automatically create Hotmail and Yahoo email accounts. They have already generated more than 15,000 bogus Hotmail accounts, according to security company BitDefender. The company says that a new threat, dubbed Trojan.Spammer.HotLan.A, is using automatically generated Yahoo and Hotmail accounts to send out spam email, which suggests that spammers have found a way to overcome Microsoft's and Yahoo's CAPTCHA systems."
It's the Mechanical Turk approach. Amazon is doing it.
Agreed. It's the 'myspace' of the 'free' email providers. The irony is that it had to be easy to use, and therefore abuse, so that kids can could use it. But now they all use MSN Messenger... Time for an update?
The time has surely passed when M$, Yahoo et al needed huge numbers of email subscribers to prove how important they were.
How about a self-policing system? Rather than the typical 'black hole' that 'abuse@...' normally leads to, one could have an automated voting system. If 'n' people complain about 'x' address, then wham, it's blocked. Could check for individual IPs, or make people mail respond to a challenge, to check that it was real people complaining, and not a botnet...
Would enough people participate, though? I know I don't try and get all the spam I receive blocked, just the ones that get through the filter, and even then, just when I have time or the mood takes me...
One of the things I get tasked with at work is handling forum and service spam. Of all the methods I've used to deter spammers, captchas rank among the least effective. A lot of people seem to think the answer is in changing the nature of what the user has to interpret. I've had suggestions ranging from audio captchas to math problems, and dozens of others that lead to the same kinds of problems - you're making it hard, or in some cases, impossible for legitimate users to use your service. Language barriers rank among the biggest problem. Say you have a picture of an apple, and the user is supposed to type 'apple'. It falls short when you realize the person viewing it may not speak english at all, or may have no idea how to spell 'apple' in english. Same with audio captchas.
The most effective (surprisingly) were form fields hidden with CSS so the users don't enter data in to them, but bots will. You can reject the entire post at that point. It's not universally effective (some bots will actually look at your CSS to determine if you're doing this) but it sure cuts down on a lot of bogus posts. Another method is to generate a form key of some kind, and use that to verify that the form is only good once. this slows spammers down because in order to post again and again, they have to reload the page in order to get a new key. many don't do this, and will attempt to use the same key over and over. if you use a few of these methods, and track repeat offenders, you can add them to your firewall rules so they can't even load the page. Of course, most serious spammers will use hundreds of IPs, so it's difficult to get them all.
It's important to realize that this is a fight you simply can't win - if they're serious about getting through, they'll get through. The most you can hope to achieve is to slow them down long enough to come up with an improved solution.
BeauHD. Worst editor since kdawson.
As luck would have it, I stumbled across a twist on the captcha concept while registering for a site. Instead of asking the human user to correctly enter the word displayed in an image, it presented the user with a grid of images. About half of them were of cars. The other half were cats.
The site just asked the user to check off each image representing a living thing.
Simple, and brutally effective against current AI. I can think of various tricks one can use to make the comparison more difficult as well.
How long until we're using the kind of tests we saw in Blade Runner?