Skip to content
Patch Next
Sign inAdd to your agent

← Actionable
High, CVSS 7.1amended

Vikunja has cross-tenant IDOR in kanban move-task endpoint via unauthorized body task_id

CVE-2026-55066GHSA-5pg6-m483-7vrg

What to do

Vendor fix available. Upgrade each affected package to the fixed version on its release line (code.vikunja.io/api 2.4.0), redeploy, then verify what is actually installed.

This page has no inventory attached, so it cannot say whether you are affected. A vendor fix is not proof that your deployment is fixed.

Add to your agent

Affected packages

Sources

Severity and exploitation
Exploitation
No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.
CVSS
7.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
EPSS
  • CVE-2026-55066: 0.37% estimated exploitation activity in the next 30 days; percentile 30.81 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.
Source description

As published by the source; long descriptions are shortened.

Summary The kanban endpoint POST /api/v1/projects/{project}/views/{view}/buckets/{bucket}/tasks moves a task into a bucket. The task is identified by taskid in the request body. The endpoint's authorization check (TaskBucket.CanUpdate) only verifies that the caller may update the project/view/bucket named in the URL — it never checks any permission on taskid. Any authenticated user can therefore supply another user's task ID (task IDs are a global, sequential integer space) against a kanban bucket in their own project. The server loads that victim task with no authorization check, returns its full contents in the response, and — when the target bucket is a "done" bucket — writes to the victim task's row. This is the same vulnerability class Vikunja has already remediated for task relations (CVE-2026-33676), task attachments (CVE-2026-33678), task comments (CVE-2026-33313) and CalDAV task read (CVE-2026-35598). TaskBucket is the task-child operation that was missed. --- Root cause 1.…

Dates and revisions
Published by the source
Last modified by the source
Source last checked
  1. Revision 3 · amended ·

    Amended from ghsa record GHSA-5pg6-m483-7vrg

  2. Revision 2 · amended ·

    Amended from osv record GO-2026-6308

  3. Revision 1 · created ·

    Published from osv record GHSA-5pg6-m483-7vrg

Agent brief

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2026-55066

Advisory: Vikunja has cross-tenant IDOR in kanban move-task endpoint via unauthorized body task_id
IDs: CVE-2026-55066, GHSA-5pg6-m483-7vrg
Record: https://patchnext.com/advisories/cve-2026-55066 (revision 3, source checked 26 Oct 2026, 15:28 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: code.vikunja.io/api 2.4.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go code.vikunja.io/api: affected <= 2.3.0; fixed in 2.4.0

## Suggested inspection (read-only)
- Go code.vikunja.io/api: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on code.vikunja.io/api.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-5pg6-m483-7vrg (OSV record GHSA-5pg6-m483-7vrg lists affected ranges: Go code.vikunja.io/api >=0 <2.4.0 (fixed))
- Verified: https://osv.dev/vulnerability/GO-2026-6308 (OSV record GO-2026-6308 lists affected ranges: Go code.vikunja.io/api >=0)
- Verified: https://github.com/advisories/GHSA-5pg6-m483-7vrg (GitHub-reviewed advisory GHSA-5pg6-m483-7vrg lists affected ranges: Go code.vikunja.io/api >=0 <=2.3.0)

Commands are suggestions: review each one before running it.

Loading voting…