An issue was discovered in Wekan The Open Source kanban board system up to version 18.15, fixed in 18.16. Uploaded attachments can be served with attacker-controlled Content-Type (text/html), allowing execution of attacker-supplied HTML/JS in the application's origin and enabling session/token theft and CSRF actions.
https://wekan.fi/hall-of-fame/spacebleed/
https://github.com/wekan/wekan/commit/e9a727301d7b4f1689a703503df668c0f4f4cab8
https://github.com/wekan/wekan/blob/main/CHANGELOG.md#v816-2025-11-02-wekan--release