{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-44452",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-05-06T15:49:25.192Z",
        "datePublished": "2026-07-16T22:54:42.914Z",
        "dateUpdated": "2026-07-17T14:03:52.757Z"
    },
    "containers": {
        "cna": {
            "title": "h2o is vulnerable to heap overrun",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-125",
                            "lang": "en",
                            "description": "CWE-125: Out-of-bounds Read",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-170",
                            "lang": "en",
                            "description": "CWE-170: Improper Null Termination",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "HIGH",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 5.9,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/h2o/h2o/security/advisories/GHSA-w68q-rqwx-7wvq",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/h2o/h2o/security/advisories/GHSA-w68q-rqwx-7wvq"
                },
                {
                    "name": "https://github.com/h2o/h2o/commit/8dc37cb1e6171f7f772667618ea440696fed82c3",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/h2o/h2o/commit/8dc37cb1e6171f7f772667618ea440696fed82c3"
                }
            ],
            "affected": [
                {
                    "vendor": "h2o",
                    "product": "h2o",
                    "versions": [
                        {
                            "version": "< 8dc37cb",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-07-16T22:54:42.914Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. Prior to commit 8dc37cb, when h2o receives a ClientHello message over TLS or QUIC and it contains a zero-length SNI extension, the h2o server runs over the zero-length hostname while trying to copy the hostname, assuming that it is NULL-terminated. This is a potential denial-of-service attack vector in sense that it might trigger segmentation violation. This issue has been fixed by commit 8dc37cb."
                }
            ],
            "source": {
                "advisory": "GHSA-w68q-rqwx-7wvq",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-07-17T14:03:32.725590Z",
                                "id": "CVE-2026-44452",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-07-17T14:03:52.757Z"
                }
            }
        ]
    }
}