ProFTPD Server 1.3.1, with NLS support enabled, allows remote attackers to bypass SQL injection protection mechanisms via invalid, encoded multibyte characters, which are not properly handled in (1) mod_sql_mysql and (2) mod_sql_postgres.
Improper Neutralization of Special Elements used in an SQL Command 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.