# CVE-2024-24817: User can see invitees in events created in PMs and private categories

> Unauthenticated attackers can view invitee lists for events in private Discourse categories or PMs, exposing user participation data.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 22 Feb 2024
- **Updated:** 21 Aug 2024
- **Also known as:** GHSA-wwq5-g5cp-c69f

## What is CVE-2024-24817?

CVE-2024-24817 is a medium-severity vulnerability in discourse-calendar, published on 22 Feb 2024. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Discourse Calendar adds the ability to create a dynamic calendar in the first post of a topic on the open-source discussion platform Discourse. Prior to version 0.4, event invitees created in topics in private categories or PMs (private messages) can be retrieved by anyone, even if they're not logged in. This problem is resolved in version 0.4 of the discourse-calendar plugin. While no known workaround is available, putting the site behind `login_required` will disallow this endpoint to be used by anonymous users, but logged in users can still get the list of invitees in the private topics.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2024-24817?

It affects 1 product.


Products: Discourse Calendar.

## How do I fix CVE-2024-24817?

No fix has been published for CVE-2024-24817 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-24817 being exploited?

There is no known exploitation of CVE-2024-24817 in the wild and no public exploit code.

## Other vulnerabilities in discourse-calendar

- [CVE-2024-26145](https://insights.sbomify.com/CVE-2024-26145/): Uninvited user is able to join and mark the attendance of the the private event (medium 6.5)
- [CVE-2024-45303](https://insights.sbomify.com/CVE-2024-45303/): Discourse Calendar plugin event names susceptible to XSS (medium 6.1)
- [CVE-2022-41913](https://insights.sbomify.com/CVE-2022-41913/): Discourse-calendar exposes members of hidden groups (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-24817 and fix it if it is affected.

What it is: CVE-2024-24817 is a medium-severity vulnerability in discourse-calendar, published on 22 Feb 2024. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-24817 in the wild and no public exploit code.

Affected product: discourse-calendar. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-24817/ (Markdown: https://insights.sbomify.com/CVE-2024-24817/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-24817
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-24817
- OSV: https://osv.dev/vulnerability/CVE-2024-24817

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-24817/
Summaries are generated and may contain mistakes; the official description above is the record.