CVE-2026-67528: Opf Openproject

Medium severity, CVSS 4.3. EPSS: 0.4% chance of exploitation in the next 30 days.

OpenProject is open-source, web-based project management software. Prior to 17.6.0, GET /api/v3/custom_options/:id resolved CustomOption records by global numeric id and allowed UserCustomField and GroupCustomField options without checking visible(current_user), so authenticated non-admin users could enumerate sequential custom option ids and read labels belonging to admin_only user or group custom fields. This issue is fixed in 17.6.0.

Affected products

• Opf Openproject: before 17.6.0 (fixed in 17.6.0)

Published 2026-07-30. Last modified 2026-07-31.