# CVE-2019-14827: Cross-site scripting in Moodle

> Attackers can inject JavaScript into Moodle Mustache templates via recursive rendering, potentially leading to script execution and account compromise.

- **Severity:** Medium 6.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 17 May 2021
- **Updated:** 5 Aug 2024
- **Also known as:** CVE-2018-1138, GHSA-9r7q-rgxm-f2hm, UBUNTU-CVE-2019-14827

## What is CVE-2019-14827?

CVE-2019-14827 is a medium-severity cross-site scripting vulnerability in Moodle Moodle, published on 17 May 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

A vulnerability was found in Moodle where javaScript injection was possible in some Mustache templates via recursive rendering from contexts. Mustache helper tags that were included in template contexts were not being escaped before that context was injected into another Mustache helper, which could result in script injection in some templates. This affects versions 3.7 to 3.7.1, 3.6 to 3.6.5, 3.5 to 3.5.7 and earlier unsupported versions.

Weakness: CWE-94 (Improper Control of Generation of Code)

## Which versions are affected by CVE-2019-14827?

It affects 1 product.


Products: Moodle Moodle.

## How do I fix CVE-2019-14827?

No fix has been published for CVE-2019-14827 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-14827 being exploited?

There is no known exploitation of CVE-2019-14827 in the wild and no public exploit code.

## Other vulnerabilities in Moodle Moodle

- [CVE-2006-4935](https://insights.sbomify.com/CVE-2006-4935/): File upload in n/a (critical 10.0)
- [CVE-2006-4936](https://insights.sbomify.com/CVE-2006-4936/): Moodle does not properly validate module instance id (critical 10.0)
- [CVE-2004-2233](https://insights.sbomify.com/CVE-2004-2233/): Unknown "front page vulnerability with Moodle servers" for Moodle before 1.3.2 has unknown impact and attack vectors. (critical 10.0)
- [CVE-2004-2235](https://insights.sbomify.com/CVE-2004-2235/): Cross-site scripting in n/a (critical 10.0)
- [CVE-2004-2236](https://insights.sbomify.com/CVE-2004-2236/): Other in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-14827 and fix it if it is affected.

What it is: CVE-2019-14827 is a medium-severity cross-site scripting vulnerability in Moodle Moodle, published on 17 May 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2019-14827 in the wild and no public exploit code.

Affected product: Moodle Moodle. 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-2019-14827/ (Markdown: https://insights.sbomify.com/CVE-2019-14827/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-14827
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-14827
- OSV: https://osv.dev/vulnerability/CVE-2019-14827

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-14827/
Summaries are generated and may contain mistakes; the official description above is the record.