WordPress WP-Predict Plugin v1.0 Blind SQL Injection

# Exploit Title: WordPress WP-Predict v1.0 Blind SQL Injection
# Date: 7/9/12
# Exploit Author: Chris Kellum
# Vendor Homepage: http://www.pootlepress.co.uk/
# Software Link: http://downloads.wordpress.org/plugin/wp-predict.zip
# Version: 1.0

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Vulnerability Details
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PredictId parameter in post request is vulnerable to blind SQL injection.

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Testing Details
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When attempting follow-up submissions, the plugin states that you've already voted. This can easily be circumvented by using your browser's back button.

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Injection Example
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Using Burp Suite or other proxy, intercept the post request when submitting your answer and append and 1=1 to the predictId parameter before forwarding:

predictSelection=1&predictId=1 and 1=1&postAction=submitVote&submitVote.x=70&submitVote.y=26

In the example above, the statement evaluates to true and the vote count increases by 1.

Sending a new request with "predictId=1 and 1=0" will not increase the vote count.