{
  "affected": [
    {
      "affectedData": [
        {
          "product": "n/a",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "n/a"
            }
          ]
        }
      ],
      "source": "cve@mitre.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "FastNetMon Community Edition through 1.2.9 contains an out-of-bounds read in the IPv4 packet parser. In src/simple_packet_parser_ng.cpp, after validating that the packet contains at least sizeof(ipv4_header_t) bytes (20 bytes), the code advances the local_pointer by \u00274 * ipv4_header-\u003eget_ihl()\u0027 (line 164) without validating that (a) IHL \u003e= 5 (the minimum valid value per RFC 791), or (b) 4 * IHL bytes are actually available in the packet. The IHL field is 4 bits, allowing values 0-15, so the advance can be 0-60 bytes. An IHL value of 15 with only 20 bytes validated causes a 40-byte over-read. An IHL of 0-4 causes the pointer to not advance past the IP header, resulting in the TCP/UDP header being parsed from IP header data (type confusion). This vulnerability is reachable via any packet capture interface."
    },
    {
      "lang": "es",
      "value": "FastNetMon Community Edition hasta la versi\u00f3n 1.2.9 contiene una lectura fuera de l\u00edmites en el analizador de paquetes IPv4. En src/simple_packet_parser_ng.cpp, despu\u00e9s de validar que el paquete contiene al menos sizeof(ipv4_header_t) bytes (20 bytes), el c\u00f3digo avanza el local_pointer en \u00274 * ipv4_header-\u003eget_ihl()\u0027 (l\u00ednea 164) sin validar que (a) IHL \u003e= 5 (el valor m\u00ednimo v\u00e1lido seg\u00fan RFC 791), o (b) 4 * IHL bytes est\u00e9n realmente disponibles en el paquete. El campo IHL es de 4 bits, permitiendo valores de 0 a 15, por lo que el avance puede ser de 0 a 60 bytes. Un valor IHL de 15 con solo 20 bytes validados causa una lectura excesiva de 40 bytes. Un IHL de 0-4 hace que el puntero no avance m\u00e1s all\u00e1 de la cabecera IP, lo que resulta en que la cabecera TCP/UDP se analice a partir de datos de la cabecera IP (confusi\u00f3n de tipos). Esta vulnerabilidad es alcanzable a trav\u00e9s de cualquier interfaz de captura de paquetes."
    }
  ],
  "id": "CVE-2026-48682",
  "lastModified": "2026-07-22T19:10:00.120",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.9,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 3.6,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-48682",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-06-03T16:04:36.835083Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-06-02T20:16:38.993",
  "references": [
    {
      "source": "cve@mitre.org",
      "url": "https://github.com/pavel-odintsov/fastnetmon"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://github.com/pavel-odintsov/fastnetmon/blob/master/src/simple_packet_parser_ng.cpp"
    },
    {
      "source": "cve@mitre.org",
      "url": "https://lorikeetsecurity.com/blog/fastnetmon-cve-2026-48682-ipv4-parser-oob"
    }
  ],
  "sourceIdentifier": "cve@mitre.org",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}