[OSGeo-Discuss] Some cialis spam in the wiki...

[Rene A Enguehard]

Just because a user has succeeded at the captcha does not mean he is 
indeed human. It's been proven by various researchers that beating 
captchas is entirely possible. Optical character recognition, like that 
used in flatbed scanner software, can be used with a fairly high success 
rate. Another technique is to build expert systems to evaluate the 
images. Another still is to build a map of hashes corresponding to 
captcha images with the solutions as
value.

Getting rid of spammers is a real pain. Captchas, IP bans and user 
registration limits all help but nothing really prevents it. 
Registration confirmation by humans is, unfortunately, the only way to 
be certain but not particularly convenient. The only thing I can think 
of that might work better is to build a filter layer into editing pages 
that scans the edit for words like "cialis" and if they are present 
sends an email to system administrators to confirm the edit. This would 
allow people to occasionally use banned words in legitimate uses but 
also flag spammers very quickly.

René

Markus Neteler a écrit :
> On Sun, Jul 5, 2009 at 3:02 PM, Anne Ghisla<a.ghisla at gmail.com> wrote:
>   
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>> Dave Patton ha scritto:
>>     
> ...
>   
>>> There is a MediaWiki Extension for reCaptcha [1]
>>> http://recaptcha.net/plugins/mediawiki/
>>>
>>> [1]
>>> http://recaptcha.net/learnmore.html
>>> http://en.wikipedia.org/wiki/ReCAPTCHA
>>>       
>> It is already active on new user registration, so maybe part of the spam
>> comes from human beings :S, then another way to limitate such spam is
>> ConfirmAccout extension [0], that requires sysops to confirm new users
>> one by one. This is extra load - but removing spam is extra load as well.
>>     
>
> One am one of them - please don't :)
> I am dealing with Wikis for many years. These human spammers always
> went away so far after a period. The overhead to manually delete a page
> from time to time is much less than confirming manually new users (which
> is also a non-incentive since they cannot start to hack the Wiki right
> away...). I don't mind to continue to delete those spam pages manually.
>
> Cheers
> Markus
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