CVE-2020-11055

Name: CVE-2020-11055
Creator: NVD / NIST
Published: 2020-05-07T21:15:11.733+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.4/10EPSS 0.78%

Last modified Jun 17, 2026

CVE-2020-11055 is a medium-severity vulnerability rated 5.4/10 on the CVSS scale. 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. EPSS estimates a 0.78% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

5.4/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

EPSS Probability

0.78%

51.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Bookstackapp	Bookstack	>= 0.18.0, < 0.29.2

References

http://jvn.jp/en/jp/JVN41035278/index.htmlThird Party Advisory
https://bookstackapp.com/blog/beta-release-v0-29-2/Release Notes, Vendor Advisory
https://github.com/BookStackApp/BookStack/releases/tag/v0.29.2Release Notes
https://github.com/BookStackApp/BookStack/security/advisories/GHSA-5vf7-q87h-pg6wThird Party Advisory
http://jvn.jp/en/jp/JVN41035278/index.htmlThird Party Advisory
https://bookstackapp.com/blog/beta-release-v0-29-2/Release Notes, Vendor Advisory
https://github.com/BookStackApp/BookStack/releases/tag/v0.29.2Release Notes
https://github.com/BookStackApp/BookStack/security/advisories/GHSA-5vf7-q87h-pg6wThird Party Advisory

Timeline

Published: May 7, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-11055?

How severe is CVE-2020-11055?

CVE-2020-11055 has a CVSS score of 5.4/10 (MEDIUM severity). The EPSS model estimates a 0.78% probability of exploitation in the next 30 days.

How do I fix CVE-2020-11055?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-11055?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST