Critical Vulnerability Reported in Vikunja < 2.2.1
Vikunja versions before 2.2.1 are under investigation for critical authorization flaws that could enable permission escalation and data deletion.
What happened
Vikunja before 2.2.1 reportedly contains an authorization flaw where the LinkSharing.ReadAll endpoint exposes share hashes to users with read access, enabling permission escalation to admin-level shares. Additionally, the GetTaskAttachment endpoint appears to allow attackers to download and delete all file attachments across all projects instance-wide by fetching attachments by sequential ID without verifying ownership.
The reported flaws have been assigned CVE-2026-56765 with a CVSS score of 9.8, indicating a critical severity level. The primary source for this vulnerability is the NVD entry for CVE-2026-56765, which should be consulted for the most accurate and up-to-date information.
To mitigate potential risks, it is recommended to upgrade to Vikunja 2.2.1 or later and review access controls for shared resources. Professional software engineers using Vikunja should assess their exposure by checking their current version and comparing it against the affected range. Further details and confirmations should be obtained from the primary sources.
How 0Day mitigates this
vikunja is anywhere in your dependency tree, the engineers who own the affected repositories get a push alert the moment it is flagged — no manual audit to remember to run.Read how this differs from waiting on a scanner to catch a known advisory, or see the exact, read-only access 0Day needs to do this for an organization.