CVE-2026-2206 identifies an improper access control vulnerability in WeKan, an open-source kanban board collaboration tool, affecting all versions up to 8.20. The vulnerability resides in the Administrative Repair Handler component, specifically within the server/methods/fixDuplicateLists.js file. This flaw allows an unauthenticated remote attacker to manipulate the system by bypassing access controls, potentially enabling unauthorized actions that could affect data confidentiality, integrity, and availability, albeit with limited scope. The CVSS 4.0 base score of 5.3 reflects a medium severity, indicating that exploitation requires low attack complexity and no user interaction, but does require some privileges (PR:L). The vulnerability does not require user interaction and does not affect system confidentiality, integrity, or availability to a critical extent, but still poses a risk of unauthorized access or modification of data within the application. The issue is resolved by upgrading to WeKan version 8.21, which includes a patch identified by commit 4ce181d17249778094f73d21515f7f863f554743. No public exploits have been reported, but the remote attack vector and ease of exploitation necessitate prompt remediation.

For European organizations, the impact of CVE-2026-2206 depends largely on their use of WeKan as a collaboration and project management tool. Unauthorized access or manipulation could lead to exposure or alteration of sensitive project data, disruption of workflows, and potential data integrity issues. While the vulnerability does not appear to allow full system compromise, it could facilitate lateral movement or privilege escalation if combined with other vulnerabilities. Organizations in sectors with stringent data protection requirements, such as finance, healthcare, and government, may face compliance risks if sensitive information is improperly accessed or altered. Additionally, disruption of collaboration tools can impact productivity and operational continuity. Given the remote exploitability and lack of required user interaction, the vulnerability poses a tangible risk if left unpatched, especially in environments with weak internal network segmentation or insufficient monitoring.

European organizations should immediately upgrade all affected WeKan instances to version 8.21 or later to apply the official patch. Beyond upgrading, organizations should implement strict network segmentation to limit access to WeKan servers, restricting them to trusted internal networks or VPNs. Employing Web Application Firewalls (WAFs) can help detect and block suspicious requests targeting the vulnerable endpoint. Regularly audit user privileges within WeKan to ensure least privilege principles are enforced, minimizing the impact of potential exploitation. Monitoring and logging access to the Administrative Repair Handler component can provide early detection of exploitation attempts. Additionally, organizations should conduct security assessments and penetration tests focusing on collaboration tools to identify and remediate similar access control weaknesses. Finally, maintain an up-to-date inventory of software versions to ensure timely patch management.