Re: Preventing XSS Attacks

On Wed, 2009-06-10 at 19:03 +0100, Ashley Sheridan wrote: > On Wed, 2009-06-10 at 23:17 +0530, Sudheer Satyanarayana wrote: > > Ashley Sheridan wrote: > > > On Wed, 2009-06-10 at 23:05 +0530, Sudheer Satyanarayana wrote: > > > > > >>> I've been doing a bit of reading, and I can't really understand why > > >>> XSS > > >>> is such an issue. Sure, if a user can insert a <script> tag, what > > >>> difference will that make to anyone else, as it is only on their own > > >>> browser. > > >>> > > >>> > > >> 1. User 1 logs on to the application. Fills up the form with malicious > > >> JS code in it. The server accepts the input, is stored in the database. > > >> 2. User 2 logs on to the application. Goes to the view the information > > >> stored in the database. The JS gets executed on user 2's browser. User > > >> is attacked by XSS. > > >> > > >> I hope that clarifies the question. > > >> > > >> > > >> > > > It does to a degree. So I shouldn't really worry about it in this case, > > > as input from one user will never be displayed to any other user. If it > > > was a forum or something, it would, but the search string is only ever > > > shown to the user who entered it, and never stored for later display. > > > > > > > > It is easy to slip by. I recall a website was hacked using XSS on the > > page the admin views the log entries. Just in case, you or somebody else > > tries to add the search log feature in the future, keep this at the back > > of your mind. Having the user to click on a harmful URI is ridiculously > > easy. > > > > > > > > > > -- > > > > With warm regards, > > Sudheer. S > > Business: http://binaryvibes.co.in, Tech stuff: > > http://techchorus.net, Personal: > > http://sudheer.net > > > > > Yeah, I never realised what a minefield it could be, but I've been doing > a lot of reading today! > > Thanks > Ash > www.ashleysheridan.co.uk > > So something like this would be acceptable?: $searchTerms = (isset($_REQUEST['q']))?$_REQUEST['q']:''; $searchTerms = htmlentities($searchTerms); $dbSearchTerms = mysql_real_escape_string($searchTerms); Giving me two variables, one for display output to user, the other for use in the database? Thanks Ash www.ashleysheridan.co.uk