CVE-2021-41252

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Summary

CVECVE-2021-41252
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-11-16 18:15:00 UTC
Updated2021-11-18 17:24:00 UTC
DescriptionKirby is an open source file structured CMS ### Impact Kirby's writer field stores its formatted content as HTML code. Unlike with other field types, it is not possible to escape HTML special characters against cross-site scripting (XSS) attacks, otherwise the formatting would be lost. If the user is logged in to the Panel, a harmful script can for example trigger requests to Kirby's API with the permissions of the victim. Because the writer field did not securely sanitize its contents on save, it was possible to inject malicious HTML code into the content file by sending it to Kirby's API directly without using the Panel. This malicious HTML code would then be displayed on the site frontend and executed in the browsers of site visitors and logged in users who are browsing the site. Attackers must be in your group of authenticated Panel users in order to exploit this weakness. Users who do not make use of the writer field are not affected. This issue has been patched in Kirby 3.5.8 by sanitizing all writer field contents on the backend whenever the content is modified via Kirby's API. Please update to this or a later version to fix the vulnerability.

Risk And Classification

Problem Types: CWE-79

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Getkirby Kirby All All All All

References

ReferenceSourceLinkTags
Cross-site scripting (XSS) from writer field content in the site frontend · Advisory · getkirby/kirby · GitHub CONFIRM github.com
Merge pull request from GHSA-x7j7-qp7j-hw3q · getkirby/kirby@25fc5c6 · GitHub MISC github.com
Release 3.5.8 · getkirby/kirby · GitHub MISC github.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
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