# CVE-2021-20121: Path traversal in Telus Wi-Fi Hub (PRV65B444A-S-TS)

> An authenticated attacker with physical access can read arbitrary files from the Telus Wi-Fi Hub via a crafted USB drive and web requests.

- **Severity:** Medium 4.0 (`CVSS:3.1/AV:P/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 11 Oct 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-3xvx-2gw5-hgv2

## What is CVE-2021-20121?

CVE-2021-20121 is a medium-severity path traversal vulnerability in Telus Wi-Fi Hub (PRV65B444A-S-TS), published on 11 Oct 2021. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The Telus Wi-Fi Hub (PRV65B444A-S-TS) with firmware version 3.00.20 is vulnerable to an authenticated arbitrary file read. An authenticated user with physical access to the device can read arbitrary files from the device by preparing and connecting a specially prepared USB drive to the device, and making a series of crafted requests to the device's web interface.

## Which versions are affected by CVE-2021-20121?

It affects 1 product.


Products: Telus Prv65b444a-S-Ts Firmware.

## How do I fix CVE-2021-20121?

No fix has been published for CVE-2021-20121 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-20121 being exploited?

There is no known exploitation of CVE-2021-20121 in the wild and no public exploit code.

## Other vulnerabilities in Telus Wi-Fi Hub (PRV65B444A-S-TS)

- [CVE-2021-20122](https://insights.sbomify.com/CVE-2021-20122/): Command injection in Telus Wi-Fi Hub (PRV65B444A-S-TS) (high 7.2)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-20121 and fix it if it is affected.

What it is: CVE-2021-20121 is a medium-severity path traversal vulnerability in Telus Wi-Fi Hub (PRV65B444A-S-TS), published on 11 Oct 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-20121 in the wild and no public exploit code.

Affected product: Telus Wi-Fi Hub (PRV65B444A-S-TS). 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-2021-20121/ (Markdown: https://insights.sbomify.com/CVE-2021-20121/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20121
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20121
- OSV: https://osv.dev/vulnerability/CVE-2021-20121

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-20121/
Summaries are generated and may contain mistakes; the official description above is the record.