CVE-2020-11055: medium-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.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 0.8%
In BookStack greater than or equal to 0.18.0 and less than 0.29.2, there is an XSS vulnerability in comment creation. A user with permission to create comments could POST HTML directly to the system to be saved in a comment, which would then be executed/displayed to others users viewing the comment. Through this vulnerability custom JavaScript code could be injected and therefore ran on other user machines. This most impacts scenarios where not-trusted users are given permission to create comments. This has been fixed in 0.29.2.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
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-2020-26210HIGHCross-Site Scripting in BookStackEPSS 1.2%CVE-2020-26211HIGHCross-Site Scripting in BookStackEPSS 1.1%CVE-2020-26260MEDIUMServer Side Request Forgery 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%