Due to limited development bandwidth, only the most recent release is currently supported. If you need support for previous releases, please contact support@pretalx.com.
If you find a vulnerability in pretalx, please contact support@pretalx.com. We will respond in a timely manner. If appropriate, we will work with you on further processes/publishing and mitigation. Since we are a small open source project, we will not be able to pay bounties, but we will acknowledge you in the disclosure publication.