CVE-2020-26211

Cross-Site Scripting in BookStack

Description

In BookStack before version 0.30.4, a user with permissions to edit a page could insert JavaScript code through the use of `javascript:` URIs within a link or form which would run, within the context of the current page, when clicked or submitted. Additionally, a user with permissions to edit a page could insert a particular meta tag which could be used to silently redirect users to a alternative location upon visit of a page. Dangerous content may remain in the database but will be removed before being displayed on a page. If you think this could have been exploited the linked advisory provides a SQL query to test. As a workaround without upgrading, 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 BookStack 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

Frequently Asked Questions

What is the severity of CVE-2020-26211?
CVE-2020-26211 has been scored as a high severity vulnerability.
How to fix CVE-2020-26211?
To fix CVE-2020-26211, 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-2020-26211 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-26211 is being actively exploited. 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-2020-26211?
CVE-2020-26211 affects BookStackApp BookStack.
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