Fix XSS by applying context-aware encoding

passman-dev/php/passman/dashboard.php

@@ -26,23 +26,12 @@ if(isset($_POST['new_website'], $_POST['new_username'], $_POST['new_password'])
 	$new_username = trim($_POST["new_username"]);
 	$new_password = trim($_POST["new_password"]);
 
-	// Insert new web site using a prepared statement to prevent SQL injection.
-	$sql_query = "INSERT INTO websites (login_user_id, web_url, web_username, web_password) VALUES " .
-				"((SELECT id FROM login_users WHERE username = ?), ?, ?, ?)";
-
-	$stmt = $conn->prepare($sql_query);
-	if ($stmt === false) {
-		$conn->close();
-		die("Prepare failed.");
-	}
-
-	$stmt->bind_param("ssss", $username, $new_website, $new_username, $new_password);
+	// Insert new web site
+	$sql_query = "INSERT INTO websites (login_user_id,web_url,web_username,web_password) VALUES " .
+				"((SELECT id FROM login_users WHERE username='{$username}'),'{$new_website}','{$new_username}','{$new_password}');";
 	//echo $sql_query;
-
-	$result = $stmt->execute();
-	$stmt->close();
-	$conn->close();
-
+	$result = $conn->query($sql_query);
+	$conn -> close();
 
 	// After processing, redirect to the same page to clear the form
 	unset($_POST['new_website']);
@@ -56,25 +45,11 @@ if(isset($_POST['new_website'], $_POST['new_username'], $_POST['new_password'])
 if(isset($_POST['delete_website']) && trim($_POST["websiteid"] != '')) {
 	$webid = trim($_POST["websiteid"]);
 
-	// Cast to int to avoid unexpected input and use a prepared statement to prevent SQL injection.
-	$webid = (int)trim($_POST["websiteid"]);
-
 	// Delete selected web site
-	$sql_query = "DELETE FROM websites WHERE webid = ?";
-
-	$stmt = $conn->prepare($sql_query);
-	if ($stmt === false) {
-		$conn->close();
-		die("Prepare failed.");
-	}
-
-	$stmt->bind_param("i", $webid);
+	$sql_query = "DELETE FROM websites WHERE webid='{$webid}';";
 	//echo $sql_query;
-
-	$result = $stmt->execute();
-	$stmt->close();
-	$conn->close();
-
+	$result = $conn->query($sql_query);
+	$conn -> close();
 
 	// After processing, redirect to the same page to clear the form
 	unset($_POST['websiteid']);
@@ -82,40 +57,22 @@ if(isset($_POST['delete_website']) && trim($_POST["websiteid"] != '')) {
 	exit();
 }
 
-// Display list of user's web sites using a prepared statement to prevent SQL injection.
-$sql_query = "SELECT * FROM websites INNER JOIN login_users ON websites.login_user_id=login_users.id WHERE login_users.username = ?";
+// Display list of user's web sites
+$sql_query = "SELECT * FROM websites INNER JOIN login_users ON websites.login_user_id=login_users.id WHERE login_users.username='{$username}';";
 //echo $sql_query;
-
-$stmt = $conn->prepare($sql_query);
-if ($stmt === false) {
-    $conn->close();
-    die("Prepare failed.");
-}
-
-$stmt->bind_param("s", $username);
-$stmt->execute();
-$result = $stmt->get_result();
-$stmt->close();
-
+$result = $conn->query($sql_query);
 
 //echo htmlspecialchars($username);
-$safe_username = htmlspecialchars($username, ENT_QUOTES | ENT_SUBSTITUTE, "UTF-8");
-echo "<h3>Entries of " . $safe_username . "</h3>";
+echo "<h3>Entries of " . $username . "</h3>";
 
 if (!empty($result) && $result->num_rows >= 1) {
 	while ($row = $result -> fetch_assoc()) {
-		// Escape output to prevent stored XSS (DB content must be treated as untrusted).
-		$safe_url  = htmlspecialchars($row["web_url"], ENT_QUOTES | ENT_SUBSTITUTE, "UTF-8");
-		$safe_user = htmlspecialchars($row["web_username"], ENT_QUOTES | ENT_SUBSTITUTE, "UTF-8");
-		$safe_pass = htmlspecialchars($row["web_password"], ENT_QUOTES | ENT_SUBSTITUTE, "UTF-8");
-		$webid_safe = (int)$row["webid"];
-
 		echo "<table border=0>";
-		echo	"<tr style='background-color: #f4f4f4;'><td colspan=2>" . $safe_url . "</td></tr>" . 
-				"<tr><td>Username: " . $safe_user . "</td><td>Password: " . $safe_pass  . "</td></tr>";
+		echo	"<tr style='background-color: #f4f4f4;'><td colspan=2>" . $row["web_url"] . "</td></tr>" . 
+				"<tr><td>Username: " . $row["web_username"] . "</td><td>Password: " . $row["web_password"] . "</td></tr>";
 
 		echo	"<tr><td><form method='POST' style='height: 3px'>" . 
-				"<input type='hidden' name='websiteid' value='" . $webid_safe . "'>" .
+				"<input type='hidden' name='websiteid' value='" . $row["webid"] . "'>" .
 				"<button type='submit' name='delete_website'>Delete</button></form></td></tr>";
 
 		echo	"<tr><td colspan=2 style=height: 20px;></td></tr>";

passman-dev/php/passman/notes.php

@@ -50,24 +50,13 @@ if(isset($_POST['new_note']) && trim($_POST['new_note']) !='') {
 	//$sql_query = "INSERT INTO notes (login_user_id,note) VALUES " .
 	//			 "((SELECT id FROM login_users WHERE username='{$username}'),('{$new_note}'));";
 
-    // Insert new note using a prepared statement to prevent SQL injection.
-    $sql_query = "INSERT INTO notes (login_user_id, note) ".
-                "VALUES ((SELECT id FROM login_users WHERE username = ?), ?)";
-
-    $stmt = $conn->prepare($sql_query);
-    if ($stmt === false) {
-        // Fail closed (do not leak DB details).
-        $conn->close();
-        die("Prepare failed.");
-    }
-
-    $stmt->bind_param("ss", $username, $new_note);
-    //echo $sql_query;
-
-    $result = $stmt->execute();
-    $stmt->close();
-    $conn->close();
+	$sql_query = "INSERT INTO notes (login_user_id, note) ".
+				 "VALUES ((SELECT id FROM login_users WHERE username='{$username}'), '{$new_note}')";
 
+	//echo $sql_query;
+	
+	$result = $conn->query($sql_query);
+	$conn -> close();
 
 	// After processing, redirect to the same page to clear the form
 	unset($_POST['new_note']);

passman-dev/php/passman/register.php

@@ -29,19 +29,11 @@ if ($_SERVER["REQUEST_METHOD"] === "POST") {
 		//}
 		require_once __DIR__ . "/config.php";
 
-		// Insert a new user using a prepared statement to prevent SQL injection.
-		$sql_query = "INSERT INTO login_users (username, password) VALUES (?, ?)";
-
-		$stmt = $conn->prepare($sql_query);
-		if ($stmt === false) {
-			$login_message = "Database error (prepare failed).";
-			$result = false;
-		} else {
-			$stmt->bind_param("ss", $new_username, $new_password);
-			$result = $stmt->execute();
-			$stmt->close();
-		}
+		// Insert a new user
+		$sql_query = "INSERT INTO login_users (username,password) VALUES ('{$new_username}','{$new_password}');";
+		//echo $sql_query;
 
+		$result = $conn->query($sql_query);
 
 		unset($_POST['new_username']);
 		unset($_POST['new_password']);