CVE-2026-33700: Vikunja has a Link Share Delete IDOR — Missing Project Ownership Check Allows Cross-Project Link Share Deletion

Severity: medium (CVSS 4.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-24 · updated 2026-06-17
Weakness: CWE-639

Description

Vikunja is an open-source self-hosted task management platform. Prior to version 2.2.1, the `DELETE /api/v1/projects/:project/shares/:share` endpoint does not verify that the link share belongs to the project specified in the URL. An attacker with admin access to any project can delete link shares from other projects by providing their own project ID combined with the target share ID. Version 2.2.1 patches the issue.

Affected products

go-vikunja vikunja: before 2.2.1 — fixed in 2.2.1

How to fix

Upgrade to a fixed version: go-vikunja vikunja 2.2.1. Check the vendor advisory for mitigations.

References

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