Severity: Critical
CVSS Score: 9.8
The implementation of ORDER BY and GROUP BY in Zend_Db_Select remained prone to SQL injection when a combination of SQL expressions and comments were used. This security patch provides a comprehensive solution that identifies and removes comments prior to checking validity of the statement to ensure no SQLi vectors occur. The implementation of ORDER BY and GROUP BY in Zend_Db_Select of ZF1 is vulnerable by the following SQL injection: ``` $db = Zend_Db::factory(/* options here */); $select = new Zend_Db_Select($db); $select->from('p'); $select->order("MD5(\"a(\");DELETE FROM p2; #)"); // same with group() ``` The above $select will render the following SQL statement: ``` SELECT `p`.* FROM `p` ORDER BY MD5("a(");DELETE FROM p2; #) ASC ``` instead of the correct one: ``` SELECT "p".* FROM "p" ORDER BY "MD5(""a("");DELETE FROM p2; #)" ASC ``` This security fix can be considered an improvement of the previous ZF2016-02 and ZF2014-04 advisories. As a final consideration, we recommend developers either never use user input for these operations, or filter user input thoroughly prior to invoking Zend_Db. You can use the Zend_Db_Select::quoteInto() method to filter the input data, as shown in this example: ``` $db = Zend_Db::factory(...); $input = "MD5(\"a(\");DELETE FROM p2; #)"; // user input can be an attack $order = $db->quoteInto("SQL statement for ORDER", $input); $select = new Zend_Db_Select($db); $select->from('p'); $select->order($order); // same with group() ```