See Cyber Safety

Responsible disclosure

Despite our security efforts a weakness could occur in one of our systems. If you have detected a vulnerability, please let us know. Then we can take the necessary measures as soon as possible, working together with you in an ongoing effort to keep our systems secure.

The Responsible disclosure procedure describes how to report a detected vulnerability.

A responsible disclosure can be reported using the email address:
Reports need to be clear and contain the steps necessary to reproduce the vulnerability. The steps need to be in the text of the message. Even though images, movies and other files may add to the clarification, they are routinely not opened because of security concerns regarding unsolicited attachments and links.

It may take up to five business days for us to analyze a report and find it of sufficient quality. It makes no sense to inquire about progress earlier.

We want to thank everybody who reported a vulnerability in a responsible way in our Hall of Fame.

Out of scope

The network of the University of Twente offers internet access for students, associations and starting companies hosting their websites. Although these sites are on the university's network, they are not the responsibility of the university. Responsible disclosure notifications about these sites will be forwarded, if possible. to the responsible persons. These reports do not result in an entry in the Hall of Fame and no updates on progress are provided.

Also out of scope are trivial vulnerabilities or bugs that cannot be abused. The following is a non-exhaustive list of examples of these vulnerabilities:

  • HTTP 404 codes/pages or other HTTP non-200 codes/pages and Content Spoofing/Text Injection on these pages.
  • fingerprint version banner disclosure on common/public services.
  • disclosure of known public files or directories or non-sensitive information, (e.g. robots.txt).
  • clickjacking and issues only exploitable through clickjacking.
  • lack of Secure/HTTPOnly flags on non-sensitive Cookies.
  • OPTIONS HTTP method enabled.
  • anything related to HTTP security headers, e.g.:
    • Strict-Transport-Security.
    • X-Frame-Options.
    • X-XSS-Protection.
    • X-Content-Type-Options.
    • Content-Security-Policy.
  • SSL Configuration Issues:
    • SSL forward secrecy not enabled.
    • weak / insecure cipher suites.
  • SPF, DKIM, DMARC issues.
  • host header injection.
  • reporting older versions of any software without proof of concept or working exploit.
  • information leakage in metadata.
  • Systems and protocols that can be used in DDoS attacks.