The Delivery Hero security team takes security bugs seriously. We appreciate your efforts to responsibly disclose your findings and will make every effort to acknowledge your contributions. To report a security issue, please use the responsible disclosure form on our web page. (Link)
The Delivery Hero team will send a response indicating the next steps in handling your report. After the initial reply to your report, the team will keep you informed of the progress towards a fix and full announcement and may ask for additional information or guidance. You can follow the public announcements on the repository's security page.