Comments on: These CAPTCHAs are just not working out http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/ Windows Security Topics by Mark Burnett Sat, 17 May 2008 14:13:52 +0000 http://wordpress.org/?v=2.1.3 By: MB’s Windows Security » Blog Archive » Lesson two on what not to do with a CAPTCHA http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1053 MB’s Windows Security » Blog Archive » Lesson two on what not to do with a CAPTCHA Wed, 22 Aug 2007 18:03:06 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1053 [...] two on what not to do with a CAPTCHA In my previous post on CAPTCHAs I mentioned that “…you need to make sure the end user can’t do anything to influence [...] […] two on what not to do with a CAPTCHA In my previous post on CAPTCHAs I mentioned that “…you need to make sure the end user can’t do anything to influence […]

]]> By: DrWiz http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1060 DrWiz Sat, 25 Aug 2007 03:31:28 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1060 How about checking if the user actually used the keyboard? Won't it work? How about checking if the user actually used the keyboard? Won’t it work?

]]> By: Tim http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1070 Tim Wed, 29 Aug 2007 09:25:51 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1070 actually u would not require a detabse as big as 308,915,776. take this senario, u would only realy require a database of one CAtCHA but a maximum of 308,915,776. page refreshs until the one image has been 'reached'. if u have a data base with 2 randemly chosen catchas the u would only need a apporimatly a maximum of half of (308,915,776) page refreshs since the catchas are displayed randomly. and so on. actually u would not require a detabse as big as 308,915,776. take this senario, u would only realy require a database of one CAtCHA but a maximum of 308,915,776. page refreshs until the one image has been ‘reached’. if u have a data base with 2 randemly chosen catchas the u would only need a apporimatly a maximum of half of (308,915,776) page refreshs since the catchas are displayed randomly. and so on.

]]> By: mb http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1071 mb Wed, 29 Aug 2007 14:28:36 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1071 Excellent point, thanks. Excellent point, thanks.

]]> By: Anne Kowalski » Blog Archive » Are CAPTCHAs Useless? http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1122 Anne Kowalski » Blog Archive » Are CAPTCHAs Useless? Thu, 13 Sep 2007 05:13:19 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1122 [...] These CAPTCHAs are just not working out [...] […] These CAPTCHAs are just not working out […]

]]> By: MustLive http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1238 MustLive Fri, 12 Oct 2007 15:43:07 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1238 Nice article Nice article

]]> By: MustLive http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1259 MustLive Wed, 17 Oct 2007 12:39:32 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1259 Captcha bypass test. Captcha bypass test.

]]> By: MustLive http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1260 MustLive Wed, 17 Oct 2007 12:40:09 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1260 Captcha bypass test 2. Captcha bypass test 2.

]]> By: MustLive http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1261 MustLive Wed, 17 Oct 2007 12:40:49 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1261 Captcha bypass test 3. Captcha bypass test 3.

]]> By: MustLive http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1262 MustLive Wed, 17 Oct 2007 12:51:16 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1262 Mark! Your captcha is vulnerable (as you can see from my Captcha bypass tests). Which is very ironical, because you wrote about captchas security in this article. So you need to find more secure captcha for yourself (without those weaknesses which you mentioned in this post). I'll write you an email about this hole. This captcha (plugin) will be in my Month of Bugs in Captchas. The official announcement of my new project will be very soon. Mark!

Your captcha is vulnerable (as you can see from my Captcha bypass tests). Which is very ironical, because you wrote about captchas security in this article. So you need to find more secure captcha for yourself (without those weaknesses which you mentioned in this post). I’ll write you an email about this hole.

This captcha (plugin) will be in my Month of Bugs in Captchas. The official announcement of my new project will be very soon.

]]> By: mb http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1701 mb Fri, 30 Nov 2007 16:37:35 +0000 http://xato.net/bl/2007/08/21/these-captchas-are-just-not-working-out/#comment-1701 a a

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