Wednesday, May 13, 2009

Rediff Search Engine XSS Vulnerability

This was something which was quite shocking as the series of events unfolded. I was researching up on output encoding methods to prevent against Cross Site Scripting and I experienced the full blown effect of the evils of bad/no output encoding and of course, no Input validation.

This was something I discovered on Rediff.com's search engine. When I typed in "search:followed by the Javascript alert, I received the infamous Javascript alert with simple 'XSS' written all over it. I was a little perturbed, because my NoScript said that it blocked a cross site scripting attack against taking place, but why was the alert still popping up? Then I was sure that the site was vulnerable to cross site scripting and decided to write about it. When I clicked the "Ok" on the Javascript alert box, another one popped up. This was definitely odd, I hadnt configured the alert for more than once. Then I clicked OK once more to find that there were more Javascript alerts to arrive with things like "XSS", session cookie details, "try_xss" and other alerts which I hadn't written. I then realized that rediff's search engine is scouring the web for pages with the XSS variants was executing that script on the rediff site, which was, beyond imagination and quite horrible. As I was clicking "OK" on the Javascript alert boxes new search results kept showing up and new alerts kept popping. The alerts only stopped with the end of the page.

Not only is Rediff vulnerable to XSS, Rediff has failed to encode their outputs from the search engine and is serving the xss, fresh from other websites, which have ironically, encoded their outputs.


I tried this out on a Google page, but it didn't work .

Anyone want to play around with the Search string try and enter your regular XSS reflected XSS tags check it out.

I have informed Rediff about the vulnerability, hopefully, they should rectify it soon.


Here are the series of screenshots of the xss alerts and the search results expanding each time.

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© Abhay Bhargav 2010