---
id: "CVE-2026-91984"
kind: "vulnerability"
aliases: ["CVE-2026-91984", "GHSA-w39f-h553-h2mx", "GO-2026-6755"]
title: "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"
severity: "medium"
cvss: 5.3
epss: 0.00264
exploited: false
status: "open"
category: "package"
products: [{"name": "code.vikunja.io/api", "fixed": [], "affected": "all versions", "ecosystem": "go"}]
ecosystems: ["go"]
tags: ["go", "package", "self-hosted", "vikunja"]
not_affected_if: ["already-on-v2.6.0"]
published_at: "2026-09-15T16:17:55+00:00"
first_seen_at: "2026-10-23T19:13:08+00:00"
updated_at: "2026-10-23T21:48:57+00:00"
sources: [{"source": "govuln", "url": "https://pkg.go.dev/vuln/GO-2026-6755", "first_seen_at": "2026-10-23T19:13:08+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-91984", "first_seen_at": "2026-10-23T19:13:43+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-91984", "first_seen_at": "2026-10-23T19:35:23+00:00"}]
---

# 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

The task position endpoint in code.vikunja.io/api (v1 and v2) accepts a project_view_id without checking that it belongs to the caller's tenant. An attacker can insert task position rows into project views they do not own.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- go:code.vikunja.io/api affected all versions fixed ?

## How to check

Check the version of code.vikunja.io/api in go.mod, or the running Vikunja build; affected versions are those before v2.6.0.

## Fix

Upgrade code.vikunja.io/api to v2.6.0 or later.

## Timeline

- 2026-10-23T19:13:08+00:00 govuln https://pkg.go.dev/vuln/GO-2026-6755
- 2026-10-23T19:13:43+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-91984
- 2026-10-23T19:35:23+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-91984

## From the sources

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 to standard Go module versions.

(If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.)

The additional affected modules and versions are: code.vikunja.io/api before v2.6.0.

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