CVE-2020-26210

Public Exploit
Cross-Site Scripting in BookStack

Description

In BookStack before version 0.30.4, a user with permissions to edit a page could add an attached link which would execute untrusted JavaScript code when clicked by a viewer of the page. Dangerous content may remain in the database after this update. If you think this could have been exploited the linked advisory provides a SQL query to test. As a workaround, page edit permissions could be limited to only those that are trusted until you can upgrade although this will not address existing exploitation of this vulnerability. The issue is fixed in version 0.30.4.

Category

7.7
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.43%
Vendor Advisory bookstackapp.com
Affected: BookStackApp BookStack
Published at:
Updated at:

References

Link Tags
https://github.com/BookStackApp/BookStack/security/advisories/GHSA-7p2j-4h6p-cq3h third party advisory exploit
https://github.com/BookStackApp/BookStack/commit/349162ea139556b2d25e09e155cec84e21cc9227 third party advisory patch
https://bookstackapp.com/blog/beta-release-v0-30-4/ patch vendor advisory exploit
https://github.com/BookStackApp/BookStack/releases/tag/v0.30.4 third party advisory

Frequently Asked Questions

What is the severity of CVE-2020-26210?
CVE-2020-26210 has been scored as a high severity vulnerability.
How to fix CVE-2020-26210?
To fix CVE-2020-26210, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-26210 being actively exploited in the wild?
It is possible that CVE-2020-26210 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-26210?
CVE-2020-26210 affects BookStackApp BookStack.
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