{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-63385",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-07-16T17:39:30.171Z",
        "datePublished": "2026-08-20T17:55:36.214Z",
        "dateUpdated": "2026-08-21T21:46:26.752Z"
    },
    "containers": {
        "cna": {
            "title": "Libevent: HTTP header handling bugs create risk of access control bypass.",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-444",
                            "lang": "en",
                            "description": "CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "HIGH",
                        "vulnIntegrityImpact": "HIGH",
                        "vulnAvailabilityImpact": "LOW",
                        "subConfidentialityImpact": "LOW",
                        "subIntegrityImpact": "LOW",
                        "subAvailabilityImpact": "NONE",
                        "baseScore": 9.2,
                        "baseSeverity": "CRITICAL",
                        "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:L/SI:L/SA:N",
                        "version": "4.0"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/libevent/libevent/security/advisories/GHSA-jcwh-pvf2-73p2",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/libevent/libevent/security/advisories/GHSA-jcwh-pvf2-73p2"
                },
                {
                    "name": "https://github.com/libevent/libevent/commit/758be0c0f69c1934ef9a84ab39e9f9e5fde2e6d0",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/libevent/libevent/commit/758be0c0f69c1934ef9a84ab39e9f9e5fde2e6d0"
                },
                {
                    "name": "https://github.com/libevent/libevent/commit/9170dd35e64714613e8d13b290587cfc28e258e2",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/libevent/libevent/commit/9170dd35e64714613e8d13b290587cfc28e258e2"
                },
                {
                    "name": "https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable"
                },
                {
                    "name": "https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha"
                }
            ],
            "affected": [
                {
                    "vendor": "libevent",
                    "product": "libevent",
                    "versions": [
                        {
                            "version": ">= 2.2.0-alpha, < 2.2.2-alpha",
                            "status": "affected"
                        },
                        {
                            "version": "< 2.1.13",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-08-20T17:55:36.214Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has two HTTP parsing weaknesses in http.c. evhttp_decode_uri_internal decodes percent-encoded %00 bytes into literal NUL characters, which can cause downstream C string operations to truncate a path and bypass validation performed on a different representation. evhttp_header_is_valid_value also accepts obsolete line folding in header values containing carriage return or line feed characters, allowing a proxy and libevent to interpret headers differently and enabling header injection or access control bypass. The CRLF header acceptance is fixed in versions 2.1.13 and 2.2.2-alpha, but the reviewed patches do not clearly remediate the URI NUL-truncation condition."
                }
            ],
            "source": {
                "advisory": "GHSA-jcwh-pvf2-73p2",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-08-21T20:58:44.281954Z",
                                "id": "CVE-2026-63385",
                                "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": "2026-08-21T21:46:26.752Z"
                }
            }
        ]
    }
}