# CVE-2024-37316: Nextcloud Calendar's event create can create attachments that link to other websites

> Authenticated users can create calendar events with malicious attachments that redirect participants to external websites upon clicking.

- **Severity:** Medium 4.6 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 14 Jun 2024
- **Updated:** 2 Aug 2024
- **Also known as:** GHSA-2r7q-vfmv-79qf

## What is CVE-2024-37316?

CVE-2024-37316 is a medium-severity vulnerability in nextcloud security-advisories, published on 14 Jun 2024. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Nextcloud Calendar is a calendar app for Nextcloud. Authenticated users could create an event with manipulated attachment data leading to a bad redirect for participants when clicked. It is recommended that the Nextcloud Calendar App is upgraded to 4.6.8 or 4.7.2.

Weakness: CWE-241 (Improper Handling of Unexpected Data Type)

## Which versions are affected by CVE-2024-37316?

It affects 1 product.


Products: Nextcloud Calendar.

## How do I fix CVE-2024-37316?

No fix has been published for CVE-2024-37316 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-37316 being exploited?

There is no known exploitation of CVE-2024-37316 in the wild and no public exploit code.

## Other vulnerabilities in nextcloud security-advisories

- [CVE-2025-66550](https://insights.sbomify.com/CVE-2025-66550/): Nextcloud Calendar attachments of local files are offered to downloaded (medium 5.7)
- [CVE-2022-24838](https://insights.sbomify.com/CVE-2022-24838/): Command Injection in Appointment Emails for Nextcloud Calendar (medium 5.3)
- [CVE-2025-66511](https://insights.sbomify.com/CVE-2025-66511/): Nextcloud Calendar app used predictable proposal participant tokens (medium 4.8)
- [CVE-2018-3763](https://insights.sbomify.com/CVE-2018-3763/): Cross-site scripting in Nextcloud Calendar application (medium 4.8)
- [CVE-2026-45286](https://insights.sbomify.com/CVE-2026-45286/): Nextcloud: Calendar app leaked user identifiers via attendee suggestion endpoint (medium 4.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-37316 and fix it if it is affected.

What it is: CVE-2024-37316 is a medium-severity vulnerability in nextcloud security-advisories, published on 14 Jun 2024. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2024-37316 in the wild and no public exploit code.

Affected product: nextcloud security-advisories. 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-2024-37316/ (Markdown: https://insights.sbomify.com/CVE-2024-37316/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-37316
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-37316
- OSV: https://osv.dev/vulnerability/CVE-2024-37316

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-37316/
Summaries are generated and may contain mistakes; the official description above is the record.