---
id: "CVE-2026-111920"
kind: "vulnerability"
aliases: ["CVE-2026-111920"]
title: "Vikunja: parent project write access overrides read-only child project shares"
severity: "medium"
cvss: 5.3
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["package", "self-hosted", "vikunja"]
not_affected_if: ["no-sub-projects", "single-user"]
published_at: "2026-10-17T19:16:34+00:00"
first_seen_at: "2026-10-23T21:57:14+00:00"
updated_at: "2026-10-25T04:26:50+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-111920", "first_seen_at": "2026-10-23T21:57:14+00:00"}]
---

# Vikunja: parent project write access overrides read-only child project shares

Vikunja 2.6.0 resolves a user's project permission as the maximum across the project tree, so an explicit read-only share on a sub-project is overridden. A collaborator with write access to the parent project can modify tasks and content in the read-only child project.

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

## Timeline

- 2026-10-23T21:57:14+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-111920

## From the sources

Vikunja 2.6.0 contains a broken access control flaw in getProjectAccessForUser (pkg/models/project_access.go), which resolves a user's effective project permission as the maximum over the project tree, silently overriding explicit lower-permission shares on sub-projects. A collaborator with write access on a parent project but read-only access to a child project can modify the child project's tasks and content.

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