# CVE-2026-123503: Vikunja authorization bypass in bucket deletion

Source: https://junglewise.ai/threats/cve-2026-123503-vikunja-before-2-7-1-contains-an-improper-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-2026-123503 · Severity: medium · CVSS 5.4 · Published 2026-11-08

Vikunja is a task and project management system with kanban boards. A user with write access to a project can delete buckets (columns) on a kanban board by manipulating the URL to reference a different view, bypassing safety checks that prevent the last bucket from being deleted. This causes inconsistencies in task assignments and dangling references within the same project.

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

## Quick answers

**Is CVE-2026-123503 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-123503 being exploited in the wild.

**How severe is CVE-2026-123503?** Medium severity, with a CVSS score of 5.4, published 8 November 2026.

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

**Is there a fix for CVE-2026-123503?** 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-2026-123503 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-123503?** 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 canDoBucket authorization check verifies that a bucket's project view ID is within the requested project, but fails to validate that the bucket's actual view ID matches the view ID in the delete request URL. When Bucket.Delete is executed, it uses the view from the URL rather than the bucket's real view, allowing deletion of buckets belonging to a different view within the same project. The vulnerability requires authenticated write access to the project and is limited to data within that single project.

## 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-9xh7-5jg8-mf43](https://github.com/go-vikunja/vikunja/security/advisories/GHSA-9xh7-5jg8-mf43)
- [https://www.vulncheck.com/advisories/vikunja-before-2.7.1-improper-authorization-in-kanban-bucket-deletion](https://www.vulncheck.com/advisories/vikunja-before-2.7.1-improper-authorization-in-kanban-bucket-deletion)

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