source: https://www.securityfocus.com/bid/37973/info PostgreSQL is prone to a buffer-overflow vulnerability because the application fails to perform adequate boundary checks on user-supplied data. Attackers can exploit this issue to execute arbitrary code with elevated privileges or crash the affected application. PostgreSQL 8.0.23 is vulnerable; other versions may also be affected. testdb=# select substring(B'101010101010101010101010101010101010 10101010101',33,-15);