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CVE-2023-3347

Samba: smb2 packet signing is not enforced when "server signing = required" is set

publishedCWE-347CWE-924

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.

Technical severity5.9 mediumCVSS 3.1 · CNA: redhat
Published2023-07-20Source updated 2026-11-07
Collected2026-11-073 attributed sources

Fixes and workarounds

No remediation reported in collected sources.

Missing remediation information is not evidence that no patch exists.

Affected products and versions

ProductVersionsAuthority
Red Hat Enterprise Linux 8
Red Hat
samba
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:4.17.5-3.el8_8; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Enterprise Linux 9
Red Hat
samba
https://access.redhat.com/downloads/content/package-browser/ 		≥ 0:4.17.5-103.el9_2; < * (unaffected, rpm)
Other versions: affected 		CNA: redhat
Red Hat Enterprise Linux 6
Red Hat
samba
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 6
Red Hat
samba4
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Enterprise Linux 7
Red Hat
samba
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unaffected 		CNA: redhat
Red Hat Storage 3
Red Hat
samba
https://access.redhat.com/downloads/content/package-browser/ 		Range not reported
Other versions: unknown 		CNA: redhat

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

NVD applicability configurations (3)

These expressions retain AND/OR operators, negation, and required environmental products. A listed product is not sufficient to establish exposure when additional conditions apply.

[
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "4.17.10",
            "versionStartIncluding": "4.17.0",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "4.18.5",
            "versionStartIncluding": "4.18.0",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "OR"
  },
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:redhat:storage:3.0:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "OR"
  },
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "OR"
  }
]

CVSS assessments

Version / scoreVectorAuthority
3.1 / 5.9
medium		 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:NCNA: redhat
3.1 / 5.9
medium		 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:NNVD: [email protected]
3.1 / 5.9
medium		 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:NNVD: [email protected]

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

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