# CVE-2021-23192: Security feature bypass in samba

> An attacker can bypass DCE/RPC signature requirements in Samba by manipulating fragmented requests, potentially compromising communication integrity.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Mar 2022
- **Updated:** 3 Aug 2024
- **Also known as:** ALPINE-CVE-2021-23192, AZL-37002, AZL-8903, DEBIAN-CVE-2021-23192, ECHO-86fa-32f7-5ab6, GHSA-vffc-r23p-p6rq, UBUNTU-CVE-2021-23192

## What is CVE-2021-23192?

CVE-2021-23192 is a high-severity vulnerability in Samba Samba, published on 2 Mar 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A flaw was found in the way samba implemented DCE/RPC. If a client to a Samba server sent a very large DCE/RPC request, and chose to fragment it, an attacker could replace later fragments with their own data, bypassing the signature requirements.

Weakness: CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2021-23192?

It affects 1 product.


Products: Samba Samba.

## How do I fix CVE-2021-23192?

Apply the vendor's patch.

## Is CVE-2021-23192 being exploited?

There is no known exploitation of CVE-2021-23192 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-2021-23192 and fix it if it is affected.

What it is: CVE-2021-23192 is a high-severity vulnerability in Samba Samba, published on 2 Mar 2022. 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-2021-23192 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-2021-23192/ (Markdown: https://insights.sbomify.com/CVE-2021-23192/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-23192
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-23192
- OSV: https://osv.dev/vulnerability/CVE-2021-23192

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-23192/
Summaries are generated and may contain mistakes; the official description above is the record.