Wekan up to 8.33 :customFieldId authorization

Summaryinfo

A vulnerability classified as critical has been found in Wekan up to 8.33. This impacts an unknown function of the file /api/boards/:boardId/custom-fields/:customFieldId. The manipulation leads to authorization. This vulnerability is listed as CVE-2026-30843. The attack may be initiated remotely. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Wekan up to 8.33. It has been rated as critical. This issue affects some unknown processing of the file /api/boards/:boardId/custom-fields/:customFieldId. The manipulation with an unknown input leads to a authorization vulnerability. Using CWE to declare the problem leads to CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Wekan is an open source kanban tool built with Meteor. Versions 8.32 and 8.33 have a critical Insecure Direct Object Reference (IDOR) issue which could allow unauthorized users to modify custom fields across boards through its custom fields update endpoints, potentially leading to unauthorized data manipulation. The PUT /api/boards/:boardId/custom-fields/:customFieldId endpoint in Wekan validates that the authenticated user has access to the specified boardId, but the subsequent database update uses only the custom field's _id as a filter without confirming the field actually belongs to that board. This means an attacker who owns any board can modify custom fields on any other board by supplying a foreign custom field ID, and the same flaw exists in the POST, PUT, and DELETE endpoints for dropdown items under custom fields. The required custom field IDs can be obtained by exporting a board (which only needs read access), since the exported JSON includes the IDs of all board components. The authorization check is performed against the wrong resource, allowing cross-board custom field manipulation. This issue has been fixed in version 8.34.

It is possible to read the advisory at securitylab.github.com. The identification of this vulnerability is CVE-2026-30843 since 03/05/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit.

Upgrading to version 8.34 eliminates this vulnerability.

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Productinfo

Name

• Wekan

Version

• 8.0
• 8.1
• 8.2
• 8.3
• 8.4
• 8.5
• 8.6
• 8.7
• 8.8
• 8.9
• 8.10
• 8.11
• 8.12
• 8.13
• 8.14
• 8.15
• 8.16
• 8.17
• 8.18
• 8.19
• 8.20
• 8.21
• 8.22
• 8.23
• 8.24
• 8.25
• 8.26
• 8.27
• 8.28
• 8.29
• 8.30
• 8.31
• 8.32
• 8.33

CPE 2.3info

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• 🔒
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CPE 2.2info

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