# CVE-2021-47749: YouPHPTube <= 7.8 - Directory Traversal

> Unauthenticated attackers can read arbitrary files via path traversal in the lang parameter, exposing sensitive data.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 Jan 2026
- **Updated:** 14 May 2026
- **Also known as:** GHSA-wh68-5mwp-jcp3

## What is CVE-2021-47749?

CVE-2021-47749 is a high-severity path traversal vulnerability in YouPHPTube, published on 13 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

YouPHPTube <= 7.8 contains a local file inclusion vulnerability that allows unauthenticated attackers to access arbitrary files by manipulating the 'lang' parameter in GET requests. Attackers can exploit the path traversal flaw in locale/function.php to include and view PHP files outside the intended directory by using directory traversal sequences.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2021-47749?

It affects 1 product.


Products: Youphptube Youphptube.

## How do I fix CVE-2021-47749?

No fix has been published for CVE-2021-47749 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-47749 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47749 exists.

## Other vulnerabilities in YouPHPTube

- [CVE-2019-5151](https://insights.sbomify.com/CVE-2019-5151/): SQL injection in YouPHPTube (critical 10.0)
- [CVE-2019-18662](https://insights.sbomify.com/CVE-2019-18662/): SQL injection in n/a (critical 9.8)
- [CVE-2019-16124](https://insights.sbomify.com/CVE-2019-16124/): Missing authorization in n/a (critical 9.8)
- [CVE-2019-5150](https://insights.sbomify.com/CVE-2019-5150/): SQL injection in YouPHPTube (high 8.9)
- [CVE-2021-25874](https://insights.sbomify.com/CVE-2021-25874/): SQL injection in n/a (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-47749 and fix it if it is affected.

What it is: CVE-2021-47749 is a high-severity path traversal vulnerability in YouPHPTube, published on 13 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47749 exists.

Affected product: YouPHPTube. 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-2021-47749/ (Markdown: https://insights.sbomify.com/CVE-2021-47749/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47749
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47749
- OSV: https://osv.dev/vulnerability/CVE-2021-47749

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-47749/
Summaries are generated and may contain mistakes; the official description above is the record.