CVE-2026-116020
BookStack before 26.09.2 Incorrect Authorization via AttachmentController on Draft Pages
BookStackApp BookStack
CVSS
5.3MediumExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)No scoreNo FIRST EPSS score in this snapshot yet
What fixes it
- 26.09.2BookStackCVE List
A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.
Reports 1
1 outlet mention it. Reports are not confirmation; each links to its source.
Description
BookStack before 26.09.2 contains an incorrect authorization vulnerability in AttachmentController that allows authenticated users to access other users' draft page attachments by ID. Attackers with attachment permissions can enumerate sequential attachment IDs to download, rename, relink, or replace files on another user's unpublished draft pages.
Text from CVE List
Affected versions 1
- BookStackaffected: all versions before 26.09.2CVE List
References 5
- codeberg.org/bookstack/bookstack/commit/fcadecccda706b4ecaf9ac3f8e27defe0ebe78aeFixvia CVE List
- codeberg.org/bookstack/bookstack/releases/tag/v26.09.2Fixvia CVE List
- bookstackapp.com/blog/bookstack-release-v26-09-2/Advisoryvia CVE List
- vulncheck.com/advisories/bookstack-before-26.09.2-incorrect-authorization-via-attachmentcontroller-on-draft-pagesAdvisoryvia CVE List
- codeberg.org/bookstack/bookstack/src/tag/v26.09.1/app/Uploads/Controllers/AttachmentController.phpReferencevia CVE List