Find the FLAG and win Intigriti swag! 🏆

Rules:

• This challenge runs from 11/07/2025 4:00 PM until 18/07/2025, 11:59 PM UTC.
• Out of all correct submissions, we will draw six winners on Monday 21/07/2025:
  • Three randomly drawn correct submissions
  • Three best write-ups
• Every winner gets a €50 swag voucher for our swag shop
• The winners will be announced on our Twitter profile.
• For every 100 likes, we'll add a tip to announcement tweet.
• Join our Discord to discuss the challenge!

The solution:

• Should work on the latest version of Firefox and Chromium. Due to recent changes, the --disable-features=EscapeLtGtInAttributes startup flag is required for Chrome, and in Firefox set dom.security.html_serialization_escape_lt_gt=false in about:config (this check should says "does NOT escape").
• Should leverage a cross site scripting vulnerability on this domain.
• Shouldn't be self-XSS or related to MiTM attacks.
• Should require no user interaction.
• Should include:
• The flag in the format INTIGRITI{.*}
• The payload(s) used
• Steps to solve (short description / bullet points)
• Should be reported on the Intigriti platform.

Get started:

1. Download the challenge source code!
2. Solve it locally!
3. Repeat your attack against the challenge server.