# CVE-2017-7796: Path traversal in Firefox

> A local attacker can exploit the Windows updater's log deletion logic to delete arbitrary files named update.log, potentially aiding other exploits.

- **Severity:** Medium 4.7 (`CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/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:** Yes
- **Published:** 11 Jun 2018
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-vqcv-9479-342r

## What is CVE-2017-7796?

CVE-2017-7796 is a medium-severity path traversal vulnerability in Mozilla Firefox, published on 11 Jun 2018. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

On Windows systems, the logger run by the Windows updater deletes the file "update.log" before it runs in order to write a new log of that name. The path to this file is supplied at the command line to the updater and could be used in concert with another local exploit to delete a different file named "update.log" instead of the one intended. Note: This attack only affects Windows operating systems. Other operating systems are not affected. This vulnerability affects Firefox < 55.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2017-7796?

It affects 1 product.


Products: Mozilla Firefox.

## How do I fix CVE-2017-7796?

Upgrade to a fixed version.

## Is CVE-2017-7796 being exploited?

There is no known exploitation of CVE-2017-7796 in the wild and no public exploit code.

## 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-2017-7796 and fix it if it is affected.

What it is: CVE-2017-7796 is a medium-severity path traversal vulnerability in Mozilla Firefox, published on 11 Jun 2018. 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-2017-7796 in the wild and no public exploit code.

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-2017-7796/ (Markdown: https://insights.sbomify.com/CVE-2017-7796/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2017-7796
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2017-7796
- OSV: https://osv.dev/vulnerability/CVE-2017-7796

---
From sbomify Insights: https://insights.sbomify.com/CVE-2017-7796/
Summaries are generated and may contain mistakes; the official description above is the record.