Medium severity · published May 7, 2020
CVE-2020-11055
In BookStack greater than or equal to 0.18.0 and less than 0.29.2, there is an XSS vulnerability in comment creation
5.4
CVSS
0.8%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 56% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
BO
Bookstack · Bookstackapp
0.18.0 before 0.29.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-11055
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-11055
Third Party Advisory
http://jvn.jp/en/jp/JVN41035278/index.html
Release Notes
https://bookstackapp.com/blog/beta-release-v0-29-2/
Release Notes
https://github.com/BookStackApp/BookStack/releases/tag/v0.29.2
Third Party Advisory
https://github.com/BookStackApp/BookStack/security/advisories/GHSA-5vf7-q87h-pg6w
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