CVE-2026-86285

medium

A vulnerability was detected in BookStack up to 26.05.2.

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

4.3

4.3 (CVSS v3.1)

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

Severity source: NVD CVSS v3.1 (cna@vuldb.com)

Timeline (UTC)

Published: 2026-09-07 09:17

Modified: 2026-09-09 15:17

NVD status: Deferred

Last synced 1 day ago

Verified against the source API 2026-10-27 06:51 UTC

Exploitation

Not listed in CISA KEV (as of last catalog sync)

Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

Not reported by the source (unknown — not "none").

Weakness classification (CWE)

CWE-266 CWE-284

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

No vendor advisory or patch reference tagged by NVD. Check the references below.

References

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

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 06:51 UTC · record ↗

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