{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "0"
                  },
                  {
                    "fixed": "4.2.1"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandardRange"
              },
              {
                "range": [
                  {
                    "fixed": "646725704463839f233472453b7c8306bd1dde21"
                  }
                ],
                "source": "REFERENCES_COMMIT"
              },
              {
                "original_tag": "v4.2.1",
                "range": [
                  {
                    "fixed": "5828feb9a79e48f8d64bfd0b9ef71c7f607bfb5d"
                  }
                ],
                "source": "REFERENCES_TAG"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5828feb9a79e48f8d64bfd0b9ef71c7f607bfb5d"
            },
            {
              "fixed": "646725704463839f233472453b7c8306bd1dde21"
            }
          ],
          "repo": "https://github.com/postalsys/postal-mime",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-jh3p-792r-98gm"
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-436"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/125xxx/CVE-2026-125756.json"
  },
  "details": "postal-mime before 4.2.1 contains a parser differential vulnerability in its address parser that truncates the domain at folding whitespace or comments preceding a dot. Remote attackers can craft From headers that pass SPF/DKIM/DMARC alignment for their own subdomain while PostalMime.parse() reports a spoofed victim sender address.",
  "id": "CVE-2026-125756",
  "modified": "2026-11-11T10:30:57.778737987Z",
  "published": "2026-11-10T15:22:50.822Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/125xxx/CVE-2026-125756.json"
    },
    {
      "type": "ARTICLE",
      "url": "https://github.com/postalsys/postal-mime/blob/939a220bd518f54d98a088c315d7227e6215cae3/src/address-parser.ts#L265"
    },
    {
      "type": "FIX",
      "url": "https://github.com/postalsys/postal-mime/commit/646725704463839f233472453b7c8306bd1dde21"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/postalsys/postal-mime/releases/tag/v4.2.1"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/postalsys/postal-mime/security/advisories/GHSA-jh3p-792r-98gm"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-125756"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/postal-mime-before-4.2.1-sender-spoofing-via-address-parser-domain-truncation"
    }
  ],
  "schema_version": "1.9.2",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "postal-mime before 4.2.1 Sender Spoofing via Address Parser Domain Truncation"
}