CVE-2026-125870

MEDIUM 4.2

BookStack before 26.09.3 Broken Access Control via ImageController

CVSS Score

4.2

EPSS Score

0.0%

EPSS Percentile

0th

BookStack before 26.09.3 contains a missing authorization vulnerability in ImageController::checkImagePermission() that allows authenticated non-admin users to bypass page-level content restrictions for images whose owning page has been moved to the recycle bin, because the permission check relies on Page::getPage() which returns null for soft-deleted pages and silently skips the PageView check. Attackers can enumerate sequential image IDs via GET /images/edit/{id} to disclose metadata of restricted images, and users with image-update-all/image-delete-all privileges can rename, replace, or permanently delete images belonging to content they cannot view, persisting the damage even after the page is restored.

CWE	CWE-863
Vendor	bookstackapp
Product	bookstack
Published	Nov 12, 2026
Last Updated	Nov 12, 2026

Stay Ahead of the Next One

Get instant alerts for bookstackapp bookstack

Be the first to know when new medium vulnerabilities affecting bookstackapp bookstack are published — delivered to Slack, Telegram or Discord.

Get Free Alerts → Free · No credit card · 60 sec setup

CVSS v3 Breakdown

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

Attack Vector

Network

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None

Affected Versions

bookstackapp / bookstack

0 < 26.09.3

References

NVD ↗ CVE.org ↗ EPSS Data ↗

codeberg.org: https://codeberg.org/bookstack/bookstack/releases/tag/v26.09.3 github.com: https://github.com/BookStackApp/BookStack/releases/tag/v26.09.3 bookstackapp.com: https://www.bookstackapp.com/blog/bookstack-release-v26-09-3/ vulncheck.com: https://www.vulncheck.com/advisories/bookstack-before-broken-access-control-via-imagecontroller

Credits

CayCon