PT-2026-118059

Vikunja: Cross-tenant task-position rows can be injected into arbitrary project views via the unvalidated project view id in the task position endpoint v1 and v2 in code.vikunja.io/api. NOTE: The source advisory for this report contains additional versions that could not be automatically mapped t...

Vikunja: Cross-tenant task-position rows can be injected into arbitrary project views via the unvalidated project_view_id in the task position endpoint (v1 and v2)

Summary The task-position endpoint authorizes only the task side of the write: TaskPosition.CanUpdate delegates to Task.CanUpdate write access to the task's own project and the request body's projectviewid is never validated to belong to the task's project, nor is any access to that view required...

CVE-2026-91984 Vikunja before 2.6.0 Broken Object-Level Authorization via task-position

Vikunja before 2.6.0 fails to validate that user-supplied projectviewid in task-position requests belongs to the task's project. Authenticated attackers can insert task position rows into arbitrary other tenant project views via POST or PUT task-position endpoints...