CVE-2026-5484: Improper Access Controls in BookStackApp BookStack
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.
AI Analysis
Technical Summary
This vulnerability involves improper access controls in the chapterToMarkdown function of the app/Exports/ExportFormatter.php file within BookStackApp BookStack up to version 26.03. By manipulating the 'pages' argument, an attacker can bypass access restrictions remotely. The vendor responded promptly and released a patch in version 26.03.1 identified by commit 8a59895ba063040cc8dafd82e94024c406df3d04.
Potential Impact
Successful exploitation allows remote attackers to bypass access controls related to chapter export functionality, potentially exposing or exporting unauthorized content. The CVSS 4.0 base score is 6.9 (medium severity), indicating a significant but not critical risk.
Mitigation Recommendations
Upgrade BookStackApp BookStack to version 26.03.1 or later, which contains the official fix for this vulnerability. The vendor has provided a patch and recommends upgrading to remediate the issue.
CVE-2026-5484: Improper Access Controls in BookStackApp BookStack
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves improper access controls in the chapterToMarkdown function of the app/Exports/ExportFormatter.php file within BookStackApp BookStack up to version 26.03. By manipulating the 'pages' argument, an attacker can bypass access restrictions remotely. The vendor responded promptly and released a patch in version 26.03.1 identified by commit 8a59895ba063040cc8dafd82e94024c406df3d04.
Potential Impact
Successful exploitation allows remote attackers to bypass access controls related to chapter export functionality, potentially exposing or exporting unauthorized content. The CVSS 4.0 base score is 6.9 (medium severity), indicating a significant but not critical risk.
Mitigation Recommendations
Upgrade BookStackApp BookStack to version 26.03.1 or later, which contains the official fix for this vulnerability. The vendor has provided a patch and recommends upgrading to remediate the issue.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulDB
- Date Reserved
- 2026-04-03T13:10:53.751Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69d01c5f0a160ebd9254ff70
Added to database: 4/3/2026, 8:00:31 PM
Last enriched: 4/11/2026, 5:54:38 AM
Last updated: 5/20/2026, 4:44:40 PM
Views: 85
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