---
id: CVE-2023-3347
title: >-
  Samba: smb2 packet signing is not enforced when "server signing = required" is
  set
summary: >-
  A vulnerability was found in Samba's SMB2 packet signing mechanism. The SMB2
  packet signing is not enforced if an admin configured "server signing =
  required" or for SMB2 connections to Domain Controllers where SMB2 packet
  signing is man…
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N'
cvssSource: cna
cwe:
  - CWE-347
vendor: Red Hat
product: samba
affected:
  - samba (all versions)
  - samba (all versions)
  - samba (all versions)
  - samba (all versions)
  - samba
  - samba4
  - samba
  - samba
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2024-04-25T13:37:21.160351Z'
published: '2023-07-20'
updated: '2026-11-07'
sourceUpdated: '2026-11-07T05:01:33.544Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2023-3347'
references:
  - url: 'https://access.redhat.com/errata/RHSA-2023:4325'
    label: 'RHSA-2023:4325'
  - url: 'https://access.redhat.com/errata/RHSA-2023:4328'
    label: 'RHSA-2023:4328'
  - url: 'https://access.redhat.com/security/cve/CVE-2023-3347'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2222792'
    label: RHBZ#2222792
  - url: 'https://www.samba.org/samba/security/CVE-2023-3347.html'
tags:
  - cve.org
epss: 0.00436
epssPercentile: 0.38097
ingestedAt: '2026-11-07T05:10:28.781Z'
---

## Overview

A vulnerability was found in Samba's SMB2 packet signing mechanism. The SMB2 packet signing is not enforced if an admin configured "server signing = required" or for SMB2 connections to Domain Controllers where SMB2 packet signing is mandatory. This flaw allows an attacker to perform attacks, such as a man-in-the-middle attack, by intercepting the network traffic and modifying the SMB2 messages between client and server, affecting the integrity of the data.

## Affected

- `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.