# CVE-2020-10704: Denial of service in samba

> An unauthorized user can cause a stack overflow and denial of service in Samba when configured as an Active Directory Domain Controller.

- **Severity:** High 7.5 (`CVSS:3.1/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:** 6 May 2020
- **Updated:** 4 Aug 2024
- **Also known as:** ALPINE-CVE-2020-10704, CLSA-2025-1764151714, DEBIAN-CVE-2020-10704, ECHO-651d-aa48-5dc7, GHSA-hxwv-6335-26h5, SUSE-SU-2020:1132-1, SUSE-SU-2020:1133-1, UBUNTU-CVE-2020-10704, USN-4341-2, openSUSE-SU-2020:0601-1

## What is CVE-2020-10704?

CVE-2020-10704 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 6 May 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A flaw was found when using samba as an Active Directory Domain Controller. Due to the way samba handles certain requests as an Active Directory Domain Controller LDAP server, an unauthorized user can cause a stack overflow leading to a denial of service. The highest threat from this vulnerability is to system availability. This issue affects all samba versions before 4.10.15, before 4.11.8 and before 4.12.2.

Weakness: CWE-674 (Uncontrolled Recursion)

## Which versions are affected by CVE-2020-10704?

It affects 4 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `samba` | SUSE:Enterprise Storage 6 | All versions | 4.9.5+git.317.6d82fb3918b-3.35.1 |
| `samba` | SUSE:Linux Enterprise High Availability Extension 15 | All versions | 4.7.11+git.231.7f324c4d89e-4.40.1 |
| `samba` | SUSE:Linux Enterprise High Availability Extension 15 SP1 | All versions | 4.9.5+git.317.6d82fb3918b-3.35.1 |
| `samba` | SUSE:Linux Enterprise High Performance Computing 15-ESPOS | All versions | 4.7.11+git.231.7f324c4d89e-4.40.1 |
| `samba` | SUSE:Linux Enterprise High Performance Computing 15-LTSS | All versions | 4.7.11+git.231.7f324c4d89e-4.40.1 |
| `samba` | SUSE:Linux Enterprise Module for Basesystem 15 SP1 | All versions | 4.9.5+git.317.6d82fb3918b-3.35.1 |
| `samba` | SUSE:Linux Enterprise Module for Python 2 15 SP1 | All versions | 4.9.5+git.317.6d82fb3918b-3.35.1 |
| `samba` | SUSE:Linux Enterprise Server 15-LTSS | All versions | 4.7.11+git.231.7f324c4d89e-4.40.1 |
| `samba` | SUSE:Linux Enterprise Server for SAP Applications 15 | All versions | 4.7.11+git.231.7f324c4d89e-4.40.1 |
| `samba` | openSUSE:Leap 15.1 | All versions | 4.9.5+git.317.6d82fb3918b-lp151.2.24.1 |

Products: Debian Debian Linux, Fedoraproject Fedora, Opensuse Leap, Samba Samba.

## How do I fix CVE-2020-10704?

Upgrade to a fixed version.

## Is CVE-2020-10704 being exploited?

There is no known exploitation of CVE-2020-10704 in the wild and no public exploit code.

## Other vulnerabilities in Debian Debian Linux

- [CVE-2015-3306](https://insights.sbomify.com/CVE-2015-3306/): ProFTPD Improper Access Control (critical 10.0, exploited in the wild)
- [CVE-2025-49113](https://insights.sbomify.com/CVE-2025-49113/): RoundCube Webmail Deserialization of Untrusted Data (critical 9.9, exploited in the wild)
- [CVE-2026-24061](https://insights.sbomify.com/CVE-2026-24061/): GNU InetUtils Argument Injection (critical 9.8, exploited in the wild)
- [CVE-2025-39682](https://insights.sbomify.com/CVE-2025-39682/): Linux Kernel Improper Check for Unusual or Exceptional Conditions (critical 9.8, exploited in the wild)
- [CVE-2024-9680](https://insights.sbomify.com/CVE-2024-9680/): Mozilla Firefox Use-After-Free (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-10704 and fix it if it is affected.

What it is: CVE-2020-10704 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 6 May 2020. 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-2020-10704 in the wild and no public exploit code.

Affected product: Debian Debian 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-2020-10704/ (Markdown: https://insights.sbomify.com/CVE-2020-10704/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-10704
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-10704
- OSV: https://osv.dev/vulnerability/CVE-2020-10704

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-10704/
Summaries are generated and may contain mistakes; the official description above is the record.