CVE-2020-26260 Server Side Request Forgery in BookStack

Medium 6.4 Published 9 Dec 2020 Updated 4 Aug 2024

An attacker with page edit permissions can trigger server-side requests and access internal files via manipulated image URLs in BookStack.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2020-26260?

CVE-2020-26260 is a medium-severity server-side request forgery vulnerability in BookStackApp BookStack, published on 9 Dec 2020. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

BookStack is a platform for storing and organising information and documentation. In BookStack before version 0.30.5, a user with permissions to edit a page could set certain image URL's to manipulate functionality in the exporting system, which would allow them to make server side requests and/or have access to a wider scope of files within the BookStack file storage locations. The issue was addressed in BookStack v0.30.5. As a workaround, page edit permissions could be limited to only those that are trusted until you can upgrade.

Weakness: CWE-74

Which versions are affected by CVE-2020-26260?

It affects 1 product.

Products include Bookstackapp Bookstack.

How do I fix CVE-2020-26260?

No fix has been published for CVE-2020-26260 yet. Limit exposure of the affected software until one is available.

Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.

Is CVE-2020-26260 being exploited?

There is no known exploitation of CVE-2020-26260 in the wild and no public exploit code.

Sources

Also known as GHSA-8wfc-w2r5-x7cr.