Hello Full-Disclosure! Last week I wrote an article DoS attacks via captchas (http://websecurity.com.ua/4052/) and recently I wrote it's English version.
I published article to The Web Security Mailing List, where you can read it: DoS attacks via captchas http://www.webappsec.org/lists/websecurity/archive/2010-03/msg00083.html Captchas must protect web sites against automated requests. But as I showed in my project Month of Bugs in Captchas (http://websecurity.com.ua/category/mobic/), they badly handle with it, due to multiple Insufficient Anti-automation vulnerabilities, which allow to bypass captchas. Besides, captchas can lead to DoS attacks on the sites. In the article I told about different ways to conduct DoS attacks on the sites which are using captchas. It must be interesting as for security community, as for admins and web developers. So everyone, who interested in this subject, can read the article. Best wishes & regards, MustLive Administrator of Websecurity web site http://websecurity.com.ua _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.grok.org.uk/full-disclosure-charter.html Hosted and sponsored by Secunia - http://secunia.com/
