上传文件至 src

src/flag.php

@@ -0,0 +1,3 @@
+<?php
+$flag = 'CTF{example_flag}';
+?>

src/index.php

@@ -0,0 +1,16 @@
+<?php
+
+highlight_file(__FILE__);
+
+
+if( $_POST['a']!==$_GET['b']&&md5($_POST['a']) === md5($_GET['b'])){
+    
+    include 'flag.php';
+    
+    
+    echo $flag;
+} else {
+    
+    echo 'nononono';
+}
+?>