CVE-2020-26260: Bookstackapp Bookstack

Medium severity, CVSS 6.4. EPSS: 0.8% chance of exploitation in the next 30 days.

BookStack is a platform for storing and organising information and documentation. In BookStack before version 0.30.5, a user with permissions to edit a page could set certain image URL's to manipulate functionality in the exporting system, which would allow them to make server side requests and/or have access to a wider scope of files within the BookStack file storage locations. The issue was addressed in BookStack v0.30.5. As a workaround, page edit permissions could be limited to only those that are trusted until you can upgrade.

Affected products

• Bookstackapp Bookstack: before 0.30.5 (fixed in 0.30.5)

Published 2020-12-09. Last modified 2026-06-17.