# CVE-2023-38470: Reachable assertion in avahi_escape_label

> A reachable assertion in Avahi's label escaping function allows attackers to cause a denial of service by triggering a crash.

- **Severity:** Medium 6.2 (`CVSS:3.1/AV:L/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:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Nov 2023
- **Updated:** 28 Oct 2026
- **Also known as:** ALPINE-CVE-2023-38470, AZL-31758, AZL-34550, BELL-CVE-2023-38470, CLEANSTART-2026-FV76384, DEBIAN-CVE-2023-38470, GHSA-mg8v-g9mc-p4f8, MINI-cq24-mcr4-5hx7, OESA-2023-1758, ROOT-OS-ALPINE-318-CVE-2023-38470, UBUNTU-CVE-2023-38470, openSUSE-SU-2024:13393-1

## What is CVE-2023-38470?

CVE-2023-38470 is a medium-severity denial of service vulnerability in Redhat Enterprise Linux, published on 2 Nov 2023. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A vulnerability was found in Avahi. A reachable assertion exists in the avahi_escape_label() function.

Weakness: CWE-617 (Reachable Assertion)

## Which versions are affected by CVE-2023-38470?

It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `avahi` | openSUSE:Tumbleweed | All versions | 0.8-27.1 |

Products: Avahi Avahi, Redhat Enterprise Linux.

## How do I fix CVE-2023-38470?

Apply the vendor's patch.

## Is CVE-2023-38470 being exploited?

There is no known exploitation of CVE-2023-38470 in the wild and no public exploit code.

## Other vulnerabilities in Redhat Enterprise Linux

- [CVE-2017-6519](https://insights.sbomify.com/CVE-2017-6519/): Denial of service in n/a (critical 9.1)
- [CVE-2021-26720](https://insights.sbomify.com/CVE-2021-26720/): Path traversal in n/a (high 7.8)
- [CVE-2026-24401](https://insights.sbomify.com/CVE-2026-24401/): Avahi has Uncontrolled Recursion in lookup_handle_cname function (medium 6.5)
- [CVE-2025-68468](https://insights.sbomify.com/CVE-2025-68468/): Avahi has a reachable assertion in lookup_multicast_callback (medium 6.5)
- [CVE-2025-68471](https://insights.sbomify.com/CVE-2025-68471/): Avahi has a reachable assertion in lookup_start (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-38470 and fix it if it is affected.

What it is: CVE-2023-38470 is a medium-severity denial of service vulnerability in Redhat Enterprise Linux, published on 2 Nov 2023. 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-2023-38470 in the wild and no public exploit code.

Affected product: Redhat Enterprise 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-2023-38470/ (Markdown: https://insights.sbomify.com/CVE-2023-38470/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-38470
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-38470
- OSV: https://osv.dev/vulnerability/CVE-2023-38470

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-38470/
Summaries are generated and may contain mistakes; the official description above is the record.