Multiple SQL injection vulnerabilities in Moodle 1.8.x before 1.8.12 and 1.9.x before 1.9.8 allow remote attackers to execute arbitrary SQL commands via vectors related to (1) the add_to_log function in mod/wiki/view.php in the wiki module, or (2) "data validation in some forms elements" related to lib/form/selectgroups.php.
The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.