CVE-2023-43658

Improper escaping of user input in discourse-calendar

Description

dicourse-calendar is a plugin for the Discourse messaging platform which adds the ability to create a dynamic calendar in the first post of a topic. Improper escaping of event titles could lead to Cross-site Scripting (XSS) within the 'email preview' UI when a site has CSP disabled. Having CSP disabled is a non-default configuration, so the vast majority of sites are unaffected. This problem is resolved in the latest version of the discourse-calendar plugin. Users are advised to upgrade. Users unable to upgrade should ensure CSP is enabled on the forum.

Category

8.0
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.57%
Vendor Advisory github.com
Affected: discourse discourse-calendar
Published at:
Updated at:

References

Link Tags
https://github.com/discourse/discourse-calendar/security/advisories/GHSA-3fwj-f6ww-7hr6 vendor advisory
https://github.com/discourse/discourse-calendar/commit/9788310906febb36822d6823d14f1059c39644de patch
https://developer.mozilla.org/en-US/docs/Web/HTTP/CSP third party advisory

Frequently Asked Questions

What is the severity of CVE-2023-43658?
CVE-2023-43658 has been scored as a high severity vulnerability.
How to fix CVE-2023-43658?
To fix CVE-2023-43658, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-43658 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-43658 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-43658?
CVE-2023-43658 affects discourse discourse-calendar.
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