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

{
  "id": "2b2d0f61c3ac6558dfefa30c7d52d2ceab88ca4c342629794f5c583e7f71c06a",
  "url": "https://osv.dev/vulnerability/CVE-2023-3347",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "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 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.",
    "evidence": "osv:CVE-2023-3347",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2023-3347",
      "aliases": [
        "CVE-2023-3347"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/samba-team/samba",
              "type": "GIT",
              "events": [
                {
                  "introduced": "fbec737d9d3d992b54f52defcba62a304efef8f7"
                },
                {
                  "fixed": "5eceb0dfb4a6490da3e7fc58f4b527b16b934195"
                },
                {
                  "introduced": "a597a8767fabfe85ee0bcf869407e770a0c3e184"
                },
                {
                  "fixed": "50a9b496556c08a451d8f18707fa709de69942ec"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.17.0"
                      },
                      {
                        "fixed": "4.17.10"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "4.18.0"
                      },
                      {
                        "fixed": "4.18.5"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "samba-4.17.9",
            "samba-4.18.4",
            "samba-4.18.3",
            "samba-4.17.8",
            "samba-4.18.2",
            "samba-4.18.1",
            "samba-4.17.7",
            "ldb-2.7.2",
            "ldb-2.6.2",
            "samba-4.17.6",
            "samba-4.18.0",
            "samba-4.17.5",
            "samba-4.17.4",
            "samba-4.17.2",
            "samba-4.17.1",
            "samba-4.17.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-3347.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:38.890620091Z",
      "provider": "osv",
      "references": [
        "https://access.redhat.com/downloads/content/package-browser/",
        "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BPCSGND7LO467AJGR5DYBGZLTCGTOBCC/",
        "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OT74M42E6C36W7PQVY3OS4ZM7DVYB64Z/",
        "https://www.samba.org/samba/security/CVE-2023-3347.html",
        "https://access.redhat.com/errata/RHSA-2023:4325",
        "https://access.redhat.com/errata/RHSA-2023:4328",
        "https://access.redhat.com/security/cve/CVE-2023-3347",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/3xxx/CVE-2023-3347.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2023-3347",
        "https://security.netapp.com/advisory/ntap-20230731-0010/",
        "https://www.debian.org/security/2023/dsa-5477",
        "https://bugzilla.redhat.com/show_bug.cgi?id=2222792"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-347"
        ],
        "cna_assigner": "redhat",
        "unresolved_ranges": [
          {
            "extracted_events": [
              {
                "range": [
                  {
                    "fixed": "0:4.17.5-3.el8_8"
                  },
                  {
                    "fixed": "0:4.17.5-3.el8_8"
                  },
                  {
                    "fixed": "0:4.17.5-103.el9_2"
                  },
                  {
                    "fixed": "0:4.17.5-103.el9_2"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "InverseAffectedRanges"
              }
            ]
          }
        ],
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/3xxx/CVE-2023-3347.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2023-3347",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 506377,
  "published_at": "2023-07-20T14:54:05.525+00:00"
}