---
id: CVE-2023-42669
title: >-
  Samba: "rpcecho" development server allows denial of service via sleep() call
  on ad dc
summary: >-
  A vulnerability was found in Samba's "rpcecho" development server, a
  non-Windows RPC server used to test Samba's DCE/RPC stack elements. This
  vulnerability stems from an RPC function that can be blocked indefinitely. The
  issue arises bec…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-400
vendor: Red Hat
product: samba
affected:
  - samba >= 4.0.0 < 4.17.12
  - samba >= 4.18.0 < 4.18.8
  - samba 4.19.0
  - samba (all versions)
  - samba (all versions)
  - samba (all versions)
  - samba (all versions)
  - samba (all versions)
  - samba (all versions)
  - samba (all versions)
  - samba (all versions)
  - samba (all versions)
  - samba
  - samba4
  - samba
  - samba
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2024-04-30T14:56:59.417578Z'
published: '2023-11-06'
updated: '2026-11-07'
sourceUpdated: '2026-11-07T11:32:54.859Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2023-42669'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2023:6209'
    label: 'RHSA-2023:6209'
  - url: 'https://access.redhat.com/errata/RHSA-2023:6744'
    label: 'RHSA-2023:6744'
  - url: 'https://access.redhat.com/errata/RHSA-2023:7371'
    label: 'RHSA-2023:7371'
  - url: 'https://access.redhat.com/errata/RHSA-2023:7408'
    label: 'RHSA-2023:7408'
  - url: 'https://access.redhat.com/errata/RHSA-2023:7464'
    label: 'RHSA-2023:7464'
  - url: 'https://access.redhat.com/errata/RHSA-2023:7467'
    label: 'RHSA-2023:7467'
  - url: 'https://access.redhat.com/security/cve/CVE-2023-42669'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2241884'
    label: RHBZ#2241884
  - url: 'https://bugzilla.samba.org/show_bug.cgi?id=15474'
  - url: 'https://www.samba.org/samba/security/CVE-2023-42669.html'
tags:
  - cve.org
epss: 0.01941
epssPercentile: 0.80215
ingestedAt: '2026-11-07T12:16:41.104Z'
---

## Overview

A vulnerability was found in Samba's "rpcecho" development server, a non-Windows RPC server used to test Samba's DCE/RPC stack elements. This vulnerability stems from an RPC function that can be blocked indefinitely. The issue arises because the "rpcecho" service operates with only one worker in the main RPC task, allowing calls to the "rpcecho" server to be blocked for a specified time, causing service disruptions. This disruption is triggered by a "sleep()" call in the "dcesrv_echo_TestSleep()" function under specific conditions. Authenticated users or attackers can exploit this vulnerability to make calls to the "rpcecho" server, requesting it to block for a specified duration, effectively disrupting most services and leading to a complete denial of service on the AD DC. The DoS affects all other services as "rpcecho" runs in the main RPC task.

## Affected

- `samba >= 4.0.0 < 4.17.12`
- `samba >= 4.18.0 < 4.18.8`
- `samba 4.19.0`
- `samba (all versions)`
- `samba (all versions)`
- `samba (all versions)`
- `samba (all versions)`
- `samba (all versions)`
- `samba (all versions)`
- `samba (all versions)`
- `samba (all versions)`
- `samba (all versions)`
- `samba`
- `samba4`
- `samba`
- `samba`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

### Workarounds

To mitigate this vulnerability, disable rpcecho service on the AD DC by setting:
~~~
dcerpc endpoint servers = -rpcecho
~~~