# CVE-2023-1400: Modern Events Calendar lite < 6.5.2 - Admin+ Stored XSS

> Admin users can inject malicious scripts via unsanitized settings in the Modern Events Calendar Lite plugin, bypassing unfiltered_html restrictions.

- **Severity:** Medium 4.8 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 27 Mar 2023
- **Updated:** 23 Apr 2025
- **Also known as:** GHSA-3cw2-x5r6-wgmh

## What is CVE-2023-1400?

CVE-2023-1400 is a medium-severity cross-site scripting vulnerability in Unknown Modern Events Calendar Lite, published on 27 Mar 2023. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.

### Official description

The Modern Events Calendar Lite WordPress plugin before 6.5.2 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup).

## Which versions are affected by CVE-2023-1400?

It affects 1 product.


Products: Webnus Modern Events Calendar Lite.

## How do I fix CVE-2023-1400?

No fix has been published for CVE-2023-1400 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-1400 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-1400 exists.

## Other vulnerabilities in Unknown Modern Events Calendar Lite

- [CVE-2021-24946](https://insights.sbomify.com/CVE-2021-24946/): Modern Events Calendar < 6.1.5 - Unauthenticated Blind SQL Injection (critical 9.8)
- [CVE-2021-24149](https://insights.sbomify.com/CVE-2021-24149/): Modern Events Calendar Lite < 5.16.6 - Authenticated SQL Injection (high 8.8)
- [CVE-2021-24146](https://insights.sbomify.com/CVE-2021-24146/): Modern Events Calendar Lite < 5.16.5 - Unauthenticated Events Export (high 7.5)
- [CVE-2021-24145](https://insights.sbomify.com/CVE-2021-24145/): Modern Events Calendar Lite < 5.16.5 - Authenticated Arbitrary File Upload leading to RCE (high 7.2)
- [CVE-2021-24925](https://insights.sbomify.com/CVE-2021-24925/): Modern Events Calendar Lite < 6.1.5 - Reflected Cross-Site Scripting (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-1400 and fix it if it is affected.

What it is: CVE-2023-1400 is a medium-severity cross-site scripting vulnerability in Unknown Modern Events Calendar Lite, published on 27 Mar 2023. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-1400 exists.

Affected product: Unknown Modern Events Calendar Lite. 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-2023-1400/ (Markdown: https://insights.sbomify.com/CVE-2023-1400/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-1400
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-1400
- OSV: https://osv.dev/vulnerability/CVE-2023-1400

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-1400/
Summaries are generated and may contain mistakes; the official description above is the record.