CVE-2026-125870bookstackapp bookstack incorrect authorization
CVE-2026-125870 is a incorrect authorization in bookstackapp bookstack, rated low (2.3 on CVSS 4.0).
Why this priority: Low severity, with no exploitation signal.
Published · Updated · NVD status: Received
What it is
A permission check exists but gets the answer wrong for some callers.
How it is reached
An attacker can exploit it over the network, with an ordinary user account, and nobody has to click anything. Success also depends on conditions the attacker does not fully control.
What an attacker gains
The direct impact is limited: partial access to data or a partial outage. In practice, this kind of flaw lets an attacker reach data or actions their role should not allow.
Is it being exploited?
There is no public report of exploitation yet.
What to do
- Upgrade bookstackapp bookstack to 26.09.3 or later.
- Until it is patched, review who holds accounts that can reach it.
Description from NVD
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.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Permission checks in APIs and admin surfaces. The flaw sits between one role or tenant and another.
- Multi-tenant services. The flaw sits between one role or tenant and another.
Trust boundaries in play
- Authenticated network access. An account is needed, so exposure follows who can sign in: customers, partners or staff.
- Between one role or tenant and another. An attacker who crosses it can reach data or actions their role should not allow.
Questions to answer about your own systems
- Where does bookstackapp bookstack run in your systems, and at which version?
- Which of those instances can be reached from the internet or partner networks?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.