# CVE-2018-16853: Denial of service in samba

> A user in a Samba AD domain can crash the KDC when using the experimental MIT Kerberos build, requiring configuration changes to mitigate.

- **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:** 28 Nov 2018
- **Updated:** 5 Aug 2024
- **Also known as:** ALPINE-CVE-2018-16853, DEBIAN-CVE-2018-16853, ECHO-ad76-9b08-2235, GHSA-wggh-6fmq-953v

## What is CVE-2018-16853?

CVE-2018-16853 is a high-severity denial of service vulnerability in Samba Samba, published on 28 Nov 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Samba from version 4.7.0 has a vulnerability that allows a user in a Samba AD domain to crash the KDC when Samba is built in the non-default MIT Kerberos configuration. With this advisory the Samba Team clarify that the MIT Kerberos build of the Samba AD DC is considered experimental. Therefore the Samba Team will not issue security patches for this configuration. Additionally, Samba 4.7.12, 4.8.7 and 4.9.3 have been issued as security releases to prevent building of the AD DC with MIT Kerberos unless --with-experimental-mit-ad-dc is specified to the configure command.

Weakness: CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2018-16853?

It affects 1 product.


Products: Samba Samba.

## How do I fix CVE-2018-16853?

Change a configuration setting.

## Is CVE-2018-16853 being exploited?

There is no known exploitation of CVE-2018-16853 in the wild and no public exploit code.

## Other vulnerabilities in Samba Samba

- [CVE-2012-1182](https://insights.sbomify.com/CVE-2012-1182/): Integer overflow in n/a (critical 10.0)
- [CVE-2007-2446](https://insights.sbomify.com/CVE-2007-2446/): Memory corruption in n/a (critical 10.0)
- [CVE-2004-0600](https://insights.sbomify.com/CVE-2004-0600/): Memory corruption in n/a (critical 10.0)
- [CVE-1999-0810](https://insights.sbomify.com/CVE-1999-0810/): Denial of service in n/a (critical 10.0)
- [CVE-1999-0182](https://insights.sbomify.com/CVE-1999-0182/): Memory corruption in n/a (critical 10.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-16853 and fix it if it is affected.

What it is: CVE-2018-16853 is a high-severity denial of service vulnerability in Samba Samba, published on 28 Nov 2018. 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-2018-16853 in the wild and no public exploit code.

Affected product: Samba Samba. 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-2018-16853/ (Markdown: https://insights.sbomify.com/CVE-2018-16853/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-16853
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-16853
- OSV: https://osv.dev/vulnerability/CVE-2018-16853

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-16853/
Summaries are generated and may contain mistakes; the official description above is the record.