CVE-2026-116020
BookStack before 26.09.2 Incorrect Authorization via AttachmentController on Draft Pages
CVSS v3.1 (listed by NVD)
5.4
MEDIUM
Scored by vulncheck.com (not yet scored by NVD)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
CVSS v4.0 (listed by NVD)
5.3
MEDIUM
Scored by vulncheck.com (not yet scored by NVD)
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
CVSS (listed by CVE.org)
5.3
MEDIUM
Scored by CNA (VulnCheck) · v4.0
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
EPSS exploit probability
—
Not computed
CISA KEV
—
Not listed
Attack conditions and impact
Derived from the CNA (via NVD) CVSS 3.1 vector
NetworkLoginNo interaction
Confidentiality LIntegrity LAvailability N
| Metric | Value | Meaning |
|---|---|---|
| Attack vector AV | N | Network |
| Attack complexity AC | L | Low (easy) |
| Privileges required PR | L | Regular user |
| User interaction UI | N | None |
| Scope S | U | Unchanged |
| Confidentiality C | L | Low |
| Integrity I | L | Low |
| Availability A | N | None |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Description
NVD
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permissions can enumerate sequential attachment IDs to download, rename, relink, or replace files on another user's unpublished draft pages.
CVSS assessments
| Provider | Version | Score | Vector |
|---|---|---|---|
| NVD / [email protected] (Secondary) | 4.0 | 5.3 MEDIUM | 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 |
| NVD / [email protected] (Primary) | 3.1 | 5.4 MEDIUM | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
| CNA / VulnCheck | 4.0 | 5.3 MEDIUM | 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 / VulnCheck | 3.1 | 5.4 MEDIUM | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N |
Affected products and packages
CNA (CVE.org)
| Vendor | Product | Versions |
|---|---|---|
| BookStackApp | BookStack | affected: 0 … < 26.09.2 default: unaffected |
Linux distribution status
References (5)
- https://codeberg.org/bookstack/bookstack/commit/fcadecccda706b4ecaf9ac3f8e27defe0ebe78ae NVD, CNA patch
- https://codeberg.org/bookstack/bookstack/releases/tag/v26.09.2 NVD, CNA release-notes
- https://codeberg.org/bookstack/bookstack/src/tag/v26.09.1/app/Uploads/Controllers/AttachmentController.php NVD, CNA technical-description
- https://www.bookstackapp.com/blog/bookstack-release-v26-09-2/ NVD, CNA vendor-advisoryrelease-notes
- https://www.vulncheck.com/advisories/bookstack-before-26.09.2-incorrect-authorization-via-attachmentcontroller-on-draft-pages NVD, CNA third-party-advisory