{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-59897",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-07-07T16:40:07.984Z",
        "datePublished": "2026-07-08T16:06:11.369Z",
        "dateUpdated": "2026-07-09T13:51:31.335Z"
    },
    "containers": {
        "cna": {
            "title": "Hono: API Gateway v1 adapter can drop a distinct repeated request header value during de-duplication",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-348",
                            "lang": "en",
                            "description": "CWE-348: Use of Less Trusted Source",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "HIGH",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "NONE",
                        "baseScore": 4.8,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "LOW",
                        "integrityImpact": "LOW",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/honojs/hono/security/advisories/GHSA-xgm2-5f3f-mvvc",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/honojs/hono/security/advisories/GHSA-xgm2-5f3f-mvvc"
                },
                {
                    "name": "https://github.com/honojs/hono/commit/aa921770d09bc35970362d5a2630a878f6d982fd",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/honojs/hono/commit/aa921770d09bc35970362d5a2630a878f6d982fd"
                },
                {
                    "name": "https://github.com/honojs/hono/releases/tag/v4.12.27",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/honojs/hono/releases/tag/v4.12.27"
                }
            ],
            "affected": [
                {
                    "vendor": "honojs",
                    "product": "hono",
                    "versions": [
                        {
                            "version": ">= 4.3.3, < 4.12.27",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-07-08T16:06:11.369Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Hono is a Web application framework that provides support for any JavaScript runtime. From 4.3.3 before 4.12.27, the AWS API Gateway v1 adapter can drop a distinct repeated request header value because it de-duplicates values using a substring comparison instead of an exact match, so middleware or application logic that depends on the complete X-Forwarded-For chain, rate limiting, audit logging, or proxy-chain validation can receive incomplete data. This issue is fixed in version 4.12.27."
                }
            ],
            "source": {
                "advisory": "GHSA-xgm2-5f3f-mvvc",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-07-09T13:51:23.283182Z",
                                "id": "CVE-2026-59897",
                                "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": "2026-07-09T13:51:31.335Z"
                }
            }
        ]
    }
}