FKIE_CVE-2026-104704

Vulnerability from fkie_nvd - Published: 2026-10-08 11:16 - Updated: 2026-10-08 21:02
Severity
7.4 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Summary
Progressive Robot hMailServer 6.0.0 through 6.3.5 does not enforce TLS for outbound SMTP delivery to a mail exchanger whose DNSSEC-validated TLSA records contain no DANE-EE (usage 3) record, contrary to RFC 7672 section 2.2. The server used only DANE-EE records and treated a validated TLSA record set consisting of DANE-TA (usage 2) or otherwise unusable records as if no records were published, so delivery to such a host fell back to opportunistic TLS. An attacker with an active position on the network path between the server and the recipient's mail exchanger can suppress or break the STARTTLS negotiation and cause messages to be delivered in cleartext, where they can be read and modified.
References
cve@gitlab.comhttps://gitlab.com/hmailserver/hmailserver/-/releases/v6.3.6
cve@gitlab.comhttps://gitlab.com/hmailserver/hmailserver/-/work_items/61
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "hMailServer",
          "repo": "https://gitlab.com/hmailserver/hmailserver",
          "vendor": "Progressive Robot Ltd",
          "versions": [
            {
              "lessThan": "6.3.6",
              "status": "affected",
              "version": "6.0.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "cve@gitlab.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Progressive Robot hMailServer 6.0.0 through 6.3.5 does not enforce TLS for outbound SMTP delivery to a mail exchanger whose DNSSEC-validated TLSA records contain no DANE-EE (usage 3) record, contrary to RFC 7672 section 2.2. The server used only DANE-EE records and treated a validated TLSA record set consisting of DANE-TA (usage 2) or otherwise unusable records as if no records were published, so delivery to such a host fell back to opportunistic TLS. An attacker with an active position on the network path between the server and the recipient\u0027s mail exchanger can suppress or break the STARTTLS negotiation and cause messages to be delivered in cleartext, where they can be read and modified."
    }
  ],
  "id": "CVE-2026-104704",
  "lastModified": "2026-10-08T21:02:43.860",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.4,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 5.2,
        "source": "cve@gitlab.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-104704",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-10-08T14:25:34.254167Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-10-08T11:16:44.457",
  "references": [
    {
      "source": "cve@gitlab.com",
      "url": "https://gitlab.com/hmailserver/hmailserver/-/releases/v6.3.6"
    },
    {
      "source": "cve@gitlab.com",
      "url": "https://gitlab.com/hmailserver/hmailserver/-/work_items/61"
    }
  ],
  "sourceIdentifier": "cve@gitlab.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-319"
        }
      ],
      "source": "cve@gitlab.com",
      "type": "Secondary"
    }
  ]
}



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