CVE-2026-86285

A vulnerability was detected in BookStack up to 26.05.2. Affected by this issue 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 results in improper access controls. The attack may be launched remotely. The exploit is now public and may be used. The patch is identified as 4e406c41c4c8060a5795e74c66fb96362e54f400. It is advisable to implement a patch to correct this issue.

CVSS v3 4.3 MEDIUM
CVSS v2.0 4.0 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

4.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:S/C:P/I:N/A:N

Exploitability : 8.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
https://ashutosh-jena.in/blog/broken-access-control-in-bookstack-how-a-missing-permission-check-leaked-attachment-data
https://codeberg.org/bookstack/bookstack/commit/4e406c41c4c8060a5795e74c66fb96362e54f400
https://vuldb.com/cve/CVE-2026-86285
https://vuldb.com/submit/905693
https://vuldb.com/vuln/399445
https://vuldb.com/vuln/399445/cti

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-07 09:17

Updated : 2026-09-09 15:17

NVD link : CVE-2026-86285

Mitre link : CVE-2026-86285

CVE.ORG link : CVE-2026-86285

JSON object : View

Products Affected

No product.

CWE

CWE-266

Incorrect Privilege Assignment

CWE-284

Improper Access Control

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