# CVE-2018-11751: Security feature bypass in Puppet Agent, Puppet

> Puppet Agent failed to verify SSL peers during CRL downloads, allowing potential man-in-the-middle attacks against configuration updates.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Dec 2019
- **Updated:** 5 Aug 2024
- **Also known as:** GHSA-vvrg-mw82-38g2

## What is CVE-2018-11751?

CVE-2018-11751 is a medium-severity vulnerability in Puppet Agent, Puppet, published on 16 Dec 2019. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Previous versions of Puppet Agent didn't verify the peer in the SSL connection prior to downloading the CRL. This issue is resolved in Puppet Agent 6.4.0.

Weakness: CWE-295 (Improper Certificate Validation)

## Which versions are affected by CVE-2018-11751?

It affects 1 product.


Products: Puppet Puppet Server.

## How do I fix CVE-2018-11751?

Upgrade to a fixed version.

## Is CVE-2018-11751 being exploited?

There is no known exploitation of CVE-2018-11751 in the wild and no public exploit code.

## Other vulnerabilities in Puppet Agent, Puppet

- [CVE-2014-7170](https://insights.sbomify.com/CVE-2014-7170/): Race condition in n/a (low 1.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-11751 and fix it if it is affected.

What it is: CVE-2018-11751 is a medium-severity vulnerability in Puppet Agent, Puppet, published on 16 Dec 2019. 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-2018-11751 in the wild and no public exploit code.

Affected product: Puppet Agent, Puppet. 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-2018-11751/ (Markdown: https://insights.sbomify.com/CVE-2018-11751/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-11751
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-11751
- OSV: https://osv.dev/vulnerability/CVE-2018-11751

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-11751/
Summaries are generated and may contain mistakes; the official description above is the record.