CVE-2023-43658

16.10.2023, 22:15

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.

Cross-site Scripting

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	NIST	8 HIGH	NETWORK	LOW	LOW	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
GitHub_M	CNA	8 HIGH	NETWORK	LOW	LOW	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
CVE	ADP	---				---
CISA-ADP	ADP	---				---

Base Score

CVSS 3.x

EPSS Score

Percentile: 67%

Vendor	Product	Version
discourse	discourse_calendar	𝑥 ≤ 2023-10-16

𝑥

= Vulnerable software versions

Common Weakness Enumeration

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

References

https://developer.mozilla.org/en-US/docs/Web/HTTP/CSP

https://github.com/discourse/discourse-calendar/commit/9788310906febb36822d6823d14f1059c39644de

https://github.com/discourse/discourse-calendar/security/advisories/GHSA-3fwj-f6ww-7hr6

https://developer.mozilla.org/en-US/docs/Web/HTTP/CSP

https://github.com/discourse/discourse-calendar/commit/9788310906febb36822d6823d14f1059c39644de

https://github.com/discourse/discourse-calendar/security/advisories/GHSA-3fwj-f6ww-7hr6