# CVE-2016-4809: Denial of service in n/a

> Remote attackers can crash applications using libarchive by providing a CPIO archive with a large symlink, requiring an upgrade to libarchive.

- **Severity:** High 7.5 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 Sep 2016
- **Updated:** 6 Aug 2024
- **Also known as:** ALPINE-CVE-2016-4809, DEBIAN-CVE-2016-4809, GHSA-qv34-qvqq-q583, UBUNTU-CVE-2016-4809

## What is CVE-2016-4809?

CVE-2016-4809 is a high-severity denial of service vulnerability in Libarchive Libarchive, published on 21 Sep 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The archive_read_format_cpio_read_header function in archive_read_support_format_cpio.c in libarchive before 3.2.1 allows remote attackers to cause a denial of service (application crash) via a CPIO archive with a large symlink.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2016-4809?

It affects 9 products.


Products: Libarchive Libarchive, Oracle Linux, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Hpc Node, Redhat Enterprise Linux Hpc Node Eus, Redhat Enterprise Linux Server, Redhat Enterprise Linux Server Aus, Redhat Enterprise Linux Server Eus, Redhat Enterprise Linux Workstation.

## How do I fix CVE-2016-4809?

Upgrade to a fixed version.

## Is CVE-2016-4809 being exploited?

There is no known exploitation of CVE-2016-4809 in the wild and no public exploit code.

## Other vulnerabilities in Libarchive Libarchive

- [CVE-2024-37407](https://insights.sbomify.com/CVE-2024-37407/): Memory corruption in n/a (critical 9.1)
- [CVE-2016-1541](https://insights.sbomify.com/CVE-2016-1541/): Memory corruption in n/a (high 8.8)
- [CVE-2016-6250](https://insights.sbomify.com/CVE-2016-6250/): Integer overflow in n/a (high 8.6)
- [CVE-2025-5914](https://insights.sbomify.com/CVE-2025-5914/): Libarchive: double free at archive_read_format_rar_seek_data() in archive_read_support_format_rar.c (high 7.8)
- [CVE-2024-48957](https://insights.sbomify.com/CVE-2024-48957/): Memory corruption in n/a (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2016-4809 and fix it if it is affected.

What it is: CVE-2016-4809 is a high-severity denial of service vulnerability in Libarchive Libarchive, published on 21 Sep 2016. 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-2016-4809 in the wild and no public exploit code.

Affected product: Libarchive Libarchive. 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-2016-4809/ (Markdown: https://insights.sbomify.com/CVE-2016-4809/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2016-4809
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2016-4809
- OSV: https://osv.dev/vulnerability/CVE-2016-4809

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From sbomify Insights: https://insights.sbomify.com/CVE-2016-4809/
Summaries are generated and may contain mistakes; the official description above is the record.