# CVE-2026-123518: Vikunja authorization bypass in kanban task-bucket move

Source: https://junglewise.ai/threats/cve-2026-123518-vikunja-before-2-7-1-contains-an-incorrect-authorization  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-08. Updated: 2026-11-08  
License: CC BY 4.0 with a link back

CVE-2026-123518 · Severity: medium · CVSS 4.3 · Published 2026-11-08

Vikunja is a task management and project collaboration platform. An authenticated user with write access to two separate projects can exploit an authorization flaw to move tasks between projects' kanban buckets, breaking project isolation. This can toggle a task's completion status, corrupt bucket task counts, and cause data inconsistency across projects.

Technologies: [Vikunja](https://junglewise.ai/threats/technologies/vikunja). Vendors: [Vikunja](https://junglewise.ai/threats/vendors/vikunja).

## Quick answers

**Is CVE-2026-123518 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-123518 being exploited in the wild.

**How severe is CVE-2026-123518?** Medium severity, with a CVSS score of 4.3, published 8 November 2026.

**Which products and versions are affected?** Vikunja before 2.7.1.

**Is there a fix for CVE-2026-123518?** Yes: fixed in 2.7.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-123518 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-123518?** Check whether you run Vikunja at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in 2.7.1

## Technical details

The TaskBucket.CanUpdate method authorizes the bucket and task sides of a move operation independently but fails to verify they belong to the same project. An authenticated attacker exploits this by issuing a PUT request to move a task from one project into a kanban bucket of another project they control, persisting a cross-project task_buckets row. The vulnerability requires prior write access to at least two projects and affects the kanban endpoint which ships enabled by default.

## Affected products

- Vikunja Vikunja before 2.7.1

## Timeline

- 2026-10-22: disclosed
- 2026-11-08: advisory

## References

- [https://github.com/go-vikunja/vikunja/security/advisories/GHSA-w64q-7p4m-j8g8](https://github.com/go-vikunja/vikunja/security/advisories/GHSA-w64q-7p4m-j8g8)
- [https://www.vulncheck.com/advisories/vikunja-before-2.7.1-missing-authorization-in-kanban-task-bucket-move](https://www.vulncheck.com/advisories/vikunja-before-2.7.1-missing-authorization-in-kanban-task-bucket-move)

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