CVE-2026-55187

{
  "id": "CVE-2026-55187",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-10T22:16:43.110",
  "lastModified": "2026-10-25T15:10:00.147",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Mailpit is an email testing tool and API for developers. Prior to 1.30.2, the remediation shipped for CVE-2026-27808 is incomplete because the tools.IsInternalIP deny-list in internal/tools/net.go relies on Go's standard library classification helpers and does not block IPv6 transition mechanisms or prefixes such as NAT64, 6to4, IPv4-compatible IPv6, ISATAP, fec0::/10, and 2001:db8::/32. An attacker who can deliver email and invoke POST /api/v1/message/{ID}/link-check can coerce the Link Check API's safeDialContext path into dialing internal destinations and can use status-code and error feedback to map internal service reachability, including cloud metadata endpoints. This issue is fixed in version 1.30.2."
    },
    {
      "lang": "es",
      "value": "Mailpit es una herramienta de prueba de correo electrónico y API para desarrolladores. Antes de la versión 1.30.2, la remediación enviada para CVE-2026-27808 es incompleta porque la lista de denegación tools.IsInternalIP en internal/tools/net.go se basa en los ayudantes de clasificación de la biblioteca estándar de Go y no bloquea los mecanismos de transición o prefijos IPv6 como NAT64, 6to4, IPv6 compatible con IPv4, ISATAP, fec0::/10 y 2001:db8::/32. Un atacante que puede entregar correo electrónico e invocar POST /api/v1/message/{ID}/link-check puede forzar la ruta safeDialContext de la API de verificación de enlaces a marcar destinos internos y puede usar la retroalimentación de códigos de estado y errores para mapear la accesibilidad del servicio interno, incluyendo los puntos finales de metadatos en la nube. Este problema está solucionado en la versión 1.30.2."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "axllent",
          "product": "mailpit",
          "versions": [
            {
              "version": "< 1.30.2",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N",
          "baseScore": 5.8,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-13T15:55:02.724130Z",
          "id": "CVE-2026-55187",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-918"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/axllent/mailpit/commit/a88dadbbe1df016a35a445089ef2a362a6c2de78",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/axllent/mailpit/releases/tag/v1.30.2",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/axllent/mailpit/security/advisories/GHSA-w4mc-hhc6-xp28",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/axllent/mailpit/security/advisories/GHSA-w4mc-hhc6-xp28",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}