{
    "dataType": "CVE_RECORD",
    "cveMetadata": {
        "state": "PUBLISHED",
        "cveId": "CVE-2026-48686",
        "assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
        "assignerShortName": "mitre",
        "dateUpdated": "2026-05-26T20:59:11.887Z",
        "dateReserved": "2026-05-22T00:00:00.000Z",
        "datePublished": "2026-05-26T00:00:00.000Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
                "shortName": "mitre",
                "dateUpdated": "2026-05-26T14:46:38.784Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "FastNetMon Community Edition through 1.2.9 contains a stack-based buffer overflow in the BGP NLRI (Network Layer Reachability Information) decoder. The function decode_bgp_subnet_encoding_ipv4_raw() in src/bgp_protocol.cpp reads prefix_bit_length directly from the BGP packet (line 99) without validating it is <= 32 for IPv4 prefixes. This value is passed to how_much_bytes_we_need_for_storing_certain_subnet_mask() which computes ceil(prefix_bit_length / 8), returning up to 32 bytes for a prefix_bit_length of 255. The result is used as the length argument to memcpy() (line 106), which copies into a 4-byte uint32_t stack variable (prefix_ipv4). This causes a stack buffer overflow of up to 28 bytes, which can be exploited for arbitrary code execution. Additionally, the unvalidated prefix_bit_length is passed to convert_cidr_to_binary_netmask_local_function_copy() (line 111), where a shift of (32 - cidr) with cidr > 32 causes undefined behavior."
                }
            ],
            "affected": [
                {
                    "vendor": "n/a",
                    "product": "n/a",
                    "versions": [
                        {
                            "version": "n/a",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://github.com/pavel-odintsov/fastnetmon"
                },
                {
                    "url": "https://github.com/pavel-odintsov/fastnetmon/blob/master/src/bgp_protocol.cpp"
                },
                {
                    "url": "https://lorikeetsecurity.com/blog/fastnetmon-cve-2026-48686-bgp-nlri-stack-overflow"
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "type": "text",
                            "lang": "en",
                            "description": "n/a"
                        }
                    ]
                }
            ]
        },
        "adp": [
            {
                "problemTypes": [
                    {
                        "descriptions": [
                            {
                                "type": "CWE",
                                "cweId": "CWE-787",
                                "lang": "en",
                                "description": "CWE-787 Out-of-bounds Write"
                            }
                        ]
                    },
                    {
                        "descriptions": [
                            {
                                "type": "CWE",
                                "cweId": "CWE-120",
                                "lang": "en",
                                "description": "CWE-120 Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')"
                            }
                        ]
                    }
                ],
                "metrics": [
                    {
                        "cvssV3_1": {
                            "scope": "UNCHANGED",
                            "version": "3.1",
                            "baseScore": 9.8,
                            "attackVector": "NETWORK",
                            "baseSeverity": "CRITICAL",
                            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
                            "integrityImpact": "HIGH",
                            "userInteraction": "NONE",
                            "attackComplexity": "LOW",
                            "availabilityImpact": "HIGH",
                            "privilegesRequired": "NONE",
                            "confidentialityImpact": "HIGH"
                        }
                    },
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-05-26T20:58:47.062692Z",
                                "id": "CVE-2026-48686",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-05-26T20:59:11.887Z"
                }
            }
        ]
    },
    "dataVersion": "5.2"
}