CVE-2026-91984

Vikunja before 2.6.0 Broken Object-Level Authorization via task-position

Published Sep 15, 2026 CVSS 4.0 · 5.3 Medium EPSS < 1% KEV · Not listed
Description
Vikunja before 2.6.0 fails to validate that user-supplied project_view_id 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.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Github GHSA Github GHSA GHSA-w39f-h553-h2mx 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)
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description Vikunja before 2.6.0 fails to validate that user-supplied project_view_id 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.
Title Vikunja before 2.6.0 Broken Object-Level Authorization via task-position
First Time appeared Vikunja
Vikunja vikunja
Weaknesses CWE-639
CPEs cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*
Vendors & Products Vikunja
Vikunja vikunja
References
Metrics cvssV3_1

{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N'}

cvssV4_0

{'score': 5.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Sep 17, 2026, 7:27 PM
Reserved
Sep 15, 2026, 11:10 AM
Status
Deferred
Published
Sep 15, 2026, 4:17 PM
Modified
Sep 17, 2026, 8:18 PM