BookStack up to 26.05.2 Attachment Edit Endpoint AttachmentController.php getUpdateForm ID access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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3.9$0-$5k1.45

Summaryinfo

A vulnerability marked as problematic has been reported in BookStack up to 26.05.2. This affects the function AttachmentController::getUpdateForm of the file app/Uploads/Controllers/AttachmentController.php of the component Attachment Edit Endpoint. This manipulation of the argument ID causes access control. This vulnerability is registered as CVE-2026-86285. Remote exploitation of the attack is possible. Furthermore, an exploit is available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability was found in BookStack up to 26.05.2. It has been declared as problematic. Affected by this vulnerability is the function AttachmentController::getUpdateForm of the file app/Uploads/Controllers/AttachmentController.php of the component Attachment Edit Endpoint. The manipulation of the argument id with an unknown input leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. As an impact it is known to affect confidentiality.

The advisory is shared at ashutosh-jena.in. This vulnerability is known as CVE-2026-86285. The exploitation appears to be easy. The attack can be launched remotely. Technical details and also a public exploit are known. MITRE ATT&CK project uses the attack technique T1068 for this issue.

It is possible to download the exploit at ashutosh-jena.in. It is declared as proof-of-concept. By approaching the search of inurl:app/Uploads/Controllers/AttachmentController.php it is possible to find vulnerable targets with Google Hacking.

Applying the patch 4e406c41c4c8060a5795e74c66fb96362e54f400 is able to eliminate this problem. The bugfix is ready for download at codeberg.org.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 3.9

VulDB Base Score: 4.3
VulDB Temp Score: 3.9
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒
Google Hack: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: 4e406c41c4c8060a5795e74c66fb96362e54f400

Timelineinfo

09/06/2026 Advisory disclosed
09/06/2026 +0 days VulDB entry created
09/06/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: ashutosh-jena.in
Status: Confirmed

CVE: CVE-2026-86285 (🔒)
GCVE (CVE): GCVE-0-2026-86285
GCVE (VulDB): GCVE-100-399445
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 09/06/2026 16:29
Changes: 09/06/2026 16:29 (58)
Complete: 🔍
Submitter: MAVERICK-VF142
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #905693: BookStack 26.05.2 Missing authorization / Broken Access Control (by MAVERICK-VF142)

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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