Description
WordPress Plugin Couponer is prone to an SQL injection vulnerability because it fails to sufficiently sanitize user-supplied data before using it in an SQL query. Exploiting this issue could allow an attacker to compromise the application, access or modify data, or exploit latent vulnerabilities in the underlying database. Successful exploitation requires that "magic_quotes" directive is set to "Off". WordPress Plugin Couponer version 1.2 is vulnerable; prior versions may also be affected.
Remediation
Edit the source code to ensure that input is properly sanitised or disable the plugin until a fix is available
References
http://www.securityfocus.com/bid/49380/exploit
http://www.exploit-db.com/exploits/17759/
http://packetstormsecurity.com/files/view/104612/wpcouponer-sql.txt