CVE-2026-86285: Improper Access Controls in BookStack
CVE-2026-86285 is a medium severity vulnerability in BookStack versions 26.05.0, 26.05.1, and 26.05.2. It involves improper access controls in the AttachmentController::getUpdateForm function, allowing remote attackers to manipulate the ID argument to bypass access restrictions. A patch identified by commit 4e406c41c4c8060a5795e74c66fb96362e54f400 is available to address this issue.
AI Analysis
Technical Summary
This vulnerability affects the Attachment Edit Endpoint in BookStack's AttachmentController::getUpdateForm function. Improper access control due to manipulation of the ID parameter enables unauthorized access to attachment update forms. The issue is remotely exploitable without user interaction and has a CVSS 4.0 base score of 5.3 (medium severity). The vulnerability is present in BookStack versions 26.05.0 through 26.05.2. A patch commit has been identified to fix the issue.
Potential Impact
An attacker can remotely exploit this vulnerability to bypass access controls on attachment update forms, potentially allowing unauthorized modification or access to attachments. The CVSS score of 5.3 indicates a moderate impact with low complexity and no privileges or user interaction required.
Mitigation Recommendations
A patch identified by commit 4e406c41c4c8060a5795e74c66fb96362e54f400 is available and should be applied to affected versions 26.05.0, 26.05.1, and 26.05.2 of BookStack to remediate this vulnerability. No vendor advisory content is provided to indicate alternative mitigations or if the patch is integrated in later versions.
CVE-2026-86285: Improper Access Controls in BookStack
Description
CVE-2026-86285 is a medium severity vulnerability in BookStack versions 26.05.0, 26.05.1, and 26.05.2. It involves improper access controls in the AttachmentController::getUpdateForm function, allowing remote attackers to manipulate the ID argument to bypass access restrictions. A patch identified by commit 4e406c41c4c8060a5795e74c66fb96362e54f400 is available to address this issue.
CVSS v4.0
Score 5.3medium
Affected software
pkg:github/bookstack/bookstackcpe:2.3:a:bookstack:bookstack:*:*:*:*:*:*:*:*Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability affects the Attachment Edit Endpoint in BookStack's AttachmentController::getUpdateForm function. Improper access control due to manipulation of the ID parameter enables unauthorized access to attachment update forms. The issue is remotely exploitable without user interaction and has a CVSS 4.0 base score of 5.3 (medium severity). The vulnerability is present in BookStack versions 26.05.0 through 26.05.2. A patch commit has been identified to fix the issue.
Potential Impact
An attacker can remotely exploit this vulnerability to bypass access controls on attachment update forms, potentially allowing unauthorized modification or access to attachments. The CVSS score of 5.3 indicates a moderate impact with low complexity and no privileges or user interaction required.
Mitigation Recommendations
A patch identified by commit 4e406c41c4c8060a5795e74c66fb96362e54f400 is available and should be applied to affected versions 26.05.0, 26.05.1, and 26.05.2 of BookStack to remediate this vulnerability. No vendor advisory content is provided to indicate alternative mitigations or if the patch is integrated in later versions.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulDB
- Date Reserved
- 2026-09-06T14:24:39.026Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a9e77e3acd9273b493fb3bf
Added to database: 09/07/2026, 08:37:55 UTC
Last enriched: 09/07/2026, 08:53:21 UTC
Last updated: 09/07/2026, 08:53:21 UTC
Views: 4
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