# CVE-2020-6828: Path traversal in Firefox ESR

> A malicious Android app can overwrite files in the Firefox profile directory via crafted Intents, potentially leading to arbitrary code execution.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 24 Apr 2020
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-9562-p32f-jq35

## What is CVE-2020-6828?

CVE-2020-6828 is a high-severity path traversal vulnerability in Mozilla Firefox Esr, published on 24 Apr 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A malicious Android application could craft an Intent that would have been processed by Firefox for Android and potentially result in a file overwrite in the user's profile directory. One exploitation vector for this would be to supply a user.js file providing arbitrary malicious preference values. Control of arbitrary preferences can lead to sufficient compromise such that it is generally equivalent to arbitrary code execution.<br> *Note: This issue only affects Firefox for Android. Other operating systems are unaffected.*. This vulnerability affects Firefox ESR < 68.7.

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

## Which versions are affected by CVE-2020-6828?

It affects 1 product.


Products: Mozilla Firefox Esr.

## How do I fix CVE-2020-6828?

Upgrade to a fixed version.

## Is CVE-2020-6828 being exploited?

There is no known exploitation of CVE-2020-6828 in the wild and no public exploit code.

## Other vulnerabilities in Mozilla Firefox Esr

- [CVE-2021-4127](https://insights.sbomify.com/CVE-2021-4127/): Other in Firefox ESR (critical 9.8)
- [CVE-2023-25746](https://insights.sbomify.com/CVE-2023-25746/): Memory corruption in Firefox ESR (high 8.8)
- [CVE-2021-38495](https://insights.sbomify.com/CVE-2021-38495/): Memory corruption in Firefox ESR (high 8.8)
- [CVE-2020-15669](https://insights.sbomify.com/CVE-2020-15669/): Use after free in Firefox ESR (high 8.8)
- [CVE-2022-38476](https://insights.sbomify.com/CVE-2022-38476/): Use after free in Firefox ESR (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-6828 and fix it if it is affected.

What it is: CVE-2020-6828 is a high-severity path traversal vulnerability in Mozilla Firefox Esr, published on 24 Apr 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2020-6828 in the wild and no public exploit code.

Affected product: Mozilla Firefox Esr. 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-2020-6828/ (Markdown: https://insights.sbomify.com/CVE-2020-6828/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-6828
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-6828
- OSV: https://osv.dev/vulnerability/CVE-2020-6828

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-6828/
Summaries are generated and may contain mistakes; the official description above is the record.