# CVE-2016-4971: Path traversal in n/a

> Remote servers can write to arbitrary files via HTTP to FTP redirection, allowing attackers to modify system files.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **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:** 30 Jun 2016
- **Updated:** 6 Aug 2024
- **Also known as:** ALPINE-CVE-2016-4971, DEBIAN-CVE-2016-4971, DLA-536-1, GHSA-5w8p-rj9f-xvj7, RHSA-2016:2587, UBUNTU-CVE-2016-4971, USN-3012-1

## What is CVE-2016-4971?

CVE-2016-4971 is a high-severity path traversal vulnerability in Canonical Ubuntu Linux, published on 30 Jun 2016. 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

GNU wget before 1.18 allows remote servers to write to arbitrary files by redirecting a request from HTTP to a crafted FTP resource.

## Which versions are affected by CVE-2016-4971?

It affects 4 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `wget` | Red Hat:enterprise_linux:7::client | All versions | 0:1.14-13.el7 |
| `wget-debuginfo` | Red Hat:enterprise_linux:7::client | All versions | 0:1.14-13.el7 |
| `wget` | Red Hat:enterprise_linux:7::computenode | All versions | 0:1.14-13.el7 |
| `wget-debuginfo` | Red Hat:enterprise_linux:7::computenode | All versions | 0:1.14-13.el7 |
| `wget` | Red Hat:enterprise_linux:7::server | All versions | 0:1.14-13.el7 |
| `wget-debuginfo` | Red Hat:enterprise_linux:7::server | All versions | 0:1.14-13.el7 |
| `wget` | Red Hat:enterprise_linux:7::workstation | All versions | 0:1.14-13.el7 |
| `wget-debuginfo` | Red Hat:enterprise_linux:7::workstation | All versions | 0:1.14-13.el7 |

Products: Canonical Ubuntu Linux, Gnu Wget, Oracle Solaris, Paloaltonetworks Pan-Os.

## How do I fix CVE-2016-4971?

Upgrade to a fixed version.

## Is CVE-2016-4971 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2016-4971 exists.

Public exploit code:

- CVE-2016-4971 Wget 1.18/1.14-13.el7 Client Exploit (github_poc): https://github.com/mbadanoiu/CVE-2016-4971
- CVE-2016-4971 written in nodejs (github_poc): https://github.com/gitcollect/CVE-2016-4971
- GNU Wget < 1.18 - Arbitrary File Upload / Remote Code Execution (exploitdb)
- https://github.com/dinidhu96/IT19013756_-CVE-2016-4971- (github_poc): https://github.com/dinidhu96/IT19013756_-CVE-2016-4971-
- GNU Wget < 1.18 - Arbitrary File Upload (2) (exploitdb)

## Other vulnerabilities in Canonical Ubuntu Linux

- [CVE-2020-11651](https://insights.sbomify.com/CVE-2020-11651/): SaltStack Salt Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2020-7247](https://insights.sbomify.com/CVE-2020-7247/): OpenSMTPD Remote Code Execution (critical 9.8, exploited in the wild)
- [CVE-2019-16928](https://insights.sbomify.com/CVE-2019-16928/): Exim Out-of-bounds Write (critical 9.8, exploited in the wild)
- [CVE-2018-6789](https://insights.sbomify.com/CVE-2018-6789/): Exim Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2015-2590](https://insights.sbomify.com/CVE-2015-2590/): Oracle Java SE and Java SE Embedded Remote Code Execution (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-4971 and fix it if it is affected.

What it is: CVE-2016-4971 is a high-severity path traversal vulnerability in Canonical Ubuntu Linux, published on 30 Jun 2016. 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-2016-4971 exists.

Affected product: Canonical Ubuntu Linux. 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-2016-4971/ (Markdown: https://insights.sbomify.com/CVE-2016-4971/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-4971
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-4971
- OSV: https://osv.dev/vulnerability/CVE-2016-4971

---
From sbomify Insights: https://insights.sbomify.com/CVE-2016-4971/
Summaries are generated and may contain mistakes; the official description above is the record.