{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "range": [
                  {
                    "introduced": "0"
                  },
                  {
                    "fixed": "5.12.13"
                  }
                ],
                "source": "AFFECTED_FIELD",
                "strategy": "StandardRange"
              },
              {
                "original_tag": "SOGo-5.12.13",
                "range": [
                  {
                    "fixed": "e2ce2bdb6ee01e875da40744f23b3e17008e36e2"
                  }
                ],
                "source": "REFERENCES_TAG"
              }
            ]
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "e2ce2bdb6ee01e875da40744f23b3e17008e36e2"
            }
          ],
          "repo": "https://github.com/alinto/sogo",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-347"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/127xxx/CVE-2026-127121.json"
  },
  "details": "SOGo before 5.12.13 contains an improper cryptographic signature verification vulnerability that allows remote attackers to replace a victim's contact S/MIME certificate by sending a spoofed multipart/signed message with a mismatched signature and an impersonated From address. Attackers can deliver a crafted CMS signedData object containing their own self-signed certificate, which SOGo's UIxMailView stores on the contact card without validating signature authenticity or certificate identity, enabling subsequent encrypted communications to be decrypted with the attacker's private key.",
  "id": "CVE-2026-127121",
  "modified": "2026-11-13T02:30:33.633042659Z",
  "published": "2026-11-12T15:55:12.349Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://github.com/Alinto/sogo"
    },
    {
      "type": "FIX",
      "url": "https://github.com/Alinto/sogo/releases/tag/SOGo-5.12.13"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/127xxx/CVE-2026-127121.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-127121"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/sogo-before-s-mime-certificate-spoofing-via-uixmailview"
    }
  ],
  "schema_version": "1.9.2",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "SOGo before 5.12.13 S/MIME Certificate Spoofing via UIxMailView"
}