# CVE-2023-29538: Information disclosure in Firefox

> A WebExtension could receive local file URIs instead of extension URIs, leaking directory paths on the user's machine.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/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:** Yes
- **Published:** 2 Jun 2023
- **Updated:** 9 Jan 2025
- **Also known as:** GHSA-5mrh-6gmv-vc85, UBUNTU-CVE-2023-29538

## What is CVE-2023-29538?

CVE-2023-29538 is a medium-severity vulnerability in Mozilla Firefox, published on 2 Jun 2023. 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

Under specific circumstances a WebExtension may have received a <code>jar:file:///</code> URI instead of a <code>moz-extension:///</code> URI during a load request. This leaked directory paths on the user's machine. This vulnerability affects Firefox for Android < 112, Firefox < 112, and Focus for Android < 112.

Weakness: CWE-668 (Exposure of Resource to Wrong Sphere)

## Which versions are affected by CVE-2023-29538?

It affects 3 products.


Products: Mozilla Firefox, Mozilla Firefox Mobile, Mozilla Focus.

## How do I fix CVE-2023-29538?

Upgrade to a fixed version.

## Is CVE-2023-29538 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-29538 exists.

## Other vulnerabilities in Mozilla Firefox

- [CVE-2019-11708](https://insights.sbomify.com/CVE-2019-11708/): Mozilla Firefox and Thunderbird Sandbox Escape (critical 10.0, exploited in the wild)
- [CVE-2010-3765](https://insights.sbomify.com/CVE-2010-3765/): Mozilla Multiple Products Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2022-26486](https://insights.sbomify.com/CVE-2022-26486/): Mozilla Firefox Use-After-Free (critical 9.6, exploited in the wild)
- [CVE-2022-26485](https://insights.sbomify.com/CVE-2022-26485/): Mozilla Firefox Use-After-Free (high 8.8, exploited in the wild)
- [CVE-2019-11707](https://insights.sbomify.com/CVE-2019-11707/): Mozilla Firefox and Thunderbird Type Confusion (high 8.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-29538 and fix it if it is affected.

What it is: CVE-2023-29538 is a medium-severity vulnerability in Mozilla Firefox, published on 2 Jun 2023. An attacker can exploit it over the internet without logging in, 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-2023-29538 exists.

Affected product: Mozilla Firefox. 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-2023-29538/ (Markdown: https://insights.sbomify.com/CVE-2023-29538/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-29538
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-29538
- OSV: https://osv.dev/vulnerability/CVE-2023-29538

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-29538/
Summaries are generated and may contain mistakes; the official description above is the record.