CVE-2026-5484
BookStackApp BookStack Chapter Export ExportFormatter.php chapterToMarkdown access control
- Published
- Updated
- Reserved
- Assigned by
- VulDB
Description
A weakness has been identified in BookStackApp BookStack up to 26.03. Affected is the function chapterToMarkdown of the file app/Exports/ExportFormatter.php of the component Chapter Export Handler. Executing a manipulation of the argument pages can lead to improper access controls. It is possible to launch the attack remotely. The exploit has been made available to the public and could be used for attacks. Upgrading to version 26.03.1 is able to address this issue. This patch is called 8a59895ba063040cc8dafd82e94024c406df3d04. It is advisable to upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulDBCNA (assigner) | 4.0 | Medium6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P |
| VulDBCNA (assigner) | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:P/RL:O/RC:C |
| VulDBCNA (assigner) | 3.0 | Medium5.3 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:P/RL:O/RC:C |
| VulDBCNA (assigner) | 2.0 | Medium5.0 | AV:N/AC:L/Au:N/C:P/I:N/A:N/E:POC/RL:OF/RC:C |
| NVDNVD · Deferred | 4.0 | Medium5.5 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/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 |
- EPSS (exploitation in 30 days)
- 0.33% · top 73% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.9.
Weakness
Affected products
- affected 26.03
- unaffected 26.03.1
References (8)
- VDB-355091 | BookStackApp BookStack Chapter Export ExportFormatter.php chapterToMarkdown access control (opens in a new tab)vdb-entrytechnical-description
- VDB-355091 | CTI Indicators (IOB, IOC, TTP, IOA) (opens in a new tab)signaturepermissions-required
- Submit #781762 | BookstackApp BookStack v25.12.9 Improper Access Controls (opens in a new tab)third-party-advisory
- https://github.com/Ghufran2/CVE-Bookstack/blob/main/Permission%20Bypass%20in%20Markdown%20Chapter%20Export (opens in a new tab)exploit
- https://www.bookstackapp.com/blog/bookstack-release-v26-03-1/ (opens in a new tab)related
- https://github.com/BookStackApp/BookStack/commit/8a59895ba063040cc8dafd82e94024c406df3d04 (opens in a new tab)patch
- https://github.com/BookStackApp/BookStack/releases/tag/v26.03.1 (opens in a new tab)patch
- https://github.com/BookStackApp/BookStack/ (opens in a new tab)product
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-5484)Record last updated .