CVE-2026-40103

Vikunja is an open-source self-hosted task management platform. Prior to 2.3.0, Vikunja's scoped API token enforcement for custom project background routes is method-confused. A token with only projects.background can successfully delete a project background, while a token with only projects.background_delete is rejected. This is a scoped-token authorization bypass. This vulnerability is fixed in 2.3.0.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/go-vikunja/vikunja/commit/6a0f39b252a81fa4b19dc56dc889183acc9225ae	Patch
https://github.com/go-vikunja/vikunja/pull/2584	Issue Tracking
https://github.com/go-vikunja/vikunja/releases/tag/v2.3.0	Release Notes
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-v479-vf79-mg83	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-10 17:17

Updated : 2026-06-17 10:44

NVD link : CVE-2026-40103

Mitre link : CVE-2026-40103

CVE.ORG link : CVE-2026-40103

JSON object : View

Products Affected

vikunja

vikunja

CWE

CWE-836

Use of Password Hash Instead of Password for Authentication

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