CVE-2020-26210: high-severity vulnerability in BookStackApp BookStack
Cross-Site Scripting in BookStack
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.7epss 1.2%
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.
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N
Affected products
BookStackApp · BookStackRelated CVEs — BookStackApp BookStack
In the same product, most dangerous first.
CVE-2020-5256HIGHRemote Code Execution Through Image Uploads in BookStackEPSS 2.0%CVE-2020-26211HIGHCross-Site Scripting in BookStackEPSS 1.1%CVE-2020-26260MEDIUMServer Side Request Forgery in BookStackEPSS 0.8%CVE-2020-11055MEDIUMCross-site Scripting in BookStackEPSS 0.8%CVE-2026-67204MEDIUMBookStack < 26.05.4 Broken Access Control via Image Gallery APIEPSS 0.4%CVE-2026-5484MEDIUMBookStackApp BookStack Chapter Export ExportFormatter.php chapterToMarkdown access controlEPSS 0.3%