CVE-2026-86285

What it is

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.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. Limited direct impact.

Exploit odds

0.4% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-09-07 09:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-09-09 15:17 UTC Last updatedMost recent change to the record

Details

Published

2026-09-07 09:17 UTC

Last modified

2026-09-09 15:17 UTC

Exploit probability

0.4% · EPSS, next 30 days

Weakness

CWE-266

Record status

Deferred

Attack profile CVSS 4.0 · 2.1

Attack vector

Network

Complexity

Low

Attack requirements

None

Privileges needed

Low

User interaction

None

Confidentiality

Low

Integrity

None

Availability

None