# CVE-2022-44640: Use after free in n/a

> Remote attackers can execute arbitrary code via an invalid free in the Heimdal KDC ASN.1 codec.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:** 25 Dec 2022
- **Updated:** 15 Apr 2025
- **Also known as:** ALPINE-CVE-2022-44640, AZL-44388, CLEANSTART-2024-JK21909, DEBIAN-CVE-2022-44640, ECHO-bb12-88ef-d3a9, GHSA-88pm-hfmq-7vv4, OESA-2022-2153, UBUNTU-CVE-2022-44640

## What is CVE-2022-44640?

CVE-2022-44640 is a critical use after free vulnerability in Samba Samba, published on 25 Dec 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Heimdal before 7.7.1 allows remote attackers to execute arbitrary code because of an invalid free in the ASN.1 codec used by the Key Distribution Center (KDC).

Weakness: CWE-415 (Double Free)

## Which versions are affected by CVE-2022-44640?

It affects 2 products.


Products: Heimdal Project Heimdal, Samba Samba.

## How do I fix CVE-2022-44640?

Upgrade to a fixed version.

## Is CVE-2022-44640 being exploited?

There is no known exploitation of CVE-2022-44640 in the wild and no public exploit code.

## Other vulnerabilities in Samba Samba

- [CVE-2022-42898](https://insights.sbomify.com/CVE-2022-42898/): Integer overflow in n/a (high 8.8)
- [CVE-2022-3116](https://insights.sbomify.com/CVE-2022-3116/): Null dereference in Heimdal Software Kerberos (high 7.5)
- [CVE-2022-45142](https://insights.sbomify.com/CVE-2022-45142/): Security feature bypass in Samba (high 7.5)
- [CVE-2021-44758](https://insights.sbomify.com/CVE-2021-44758/): Null dereference in n/a (high 7.5)
- [CVE-2018-16860](https://insights.sbomify.com/CVE-2018-16860/): Auth bypass in samba (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-44640 and fix it if it is affected.

What it is: CVE-2022-44640 is a critical use after free vulnerability in Samba Samba, published on 25 Dec 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-2022-44640 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-2022-44640/ (Markdown: https://insights.sbomify.com/CVE-2022-44640/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-44640
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-44640
- OSV: https://osv.dev/vulnerability/CVE-2022-44640

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-44640/
Summaries are generated and may contain mistakes; the official description above is the record.