CVE-2026-116020 json
BookStack before 26.09.2 Incorrect Authorization via AttachmentController on Draft Pages
published 16d ago modified 4d ago also EUVD-2026-109278
- cvss
- 5.4
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 7%
- public exploits
- 0
- none known
Summary
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permissions can enumerate sequential attachment IDs to download, rename, relink, or replace files on another user's unpublished draft pages.
Patch / fix
- BookStackApp BookStack 26.09.2
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- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 4d ago
Exploit prediction
0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N |
| CNA | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
| CNA | 4.0 | 5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- BookStackApp BookStack
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
-
codeberg.org
/bookstack/bookstack/commit/fcadecccda706b4ecaf9ac3f8e27defe0ebe78ae
patch
-
bookstackapp.com
/blog/bookstack-release-v26-09-2/
vendor-advisory, release-notes
-
codeberg.org
/bookstack/bookstack/releases/tag/v26.09.2
release-notes
-
codeberg.org
/bookstack/bookstack/src/tag/v26.09.1/app/Uploads/Controllers/AttachmentController.php
technical-description
-
vulncheck.com
/advisories/bookstack-before-26.09.2-incorrect-authorization-via-attachmentcontroller-on-draft-pages
third-party-advisory
Sources
- CVE List CVE-2026-116020
- NVD CVE-2026-116020
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