{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-27700",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-02-23T17:56:51.202Z",
        "datePublished": "2026-02-25T15:01:44.681Z",
        "dateUpdated": "2026-02-27T17:01:28.403Z"
    },
    "containers": {
        "cna": {
            "title": "Hono is Vulnerable to Authentication Bypass by IP Spoofing in AWS Lambda ALB conninfo",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-345",
                            "lang": "en",
                            "description": "CWE-345: Insufficient Verification of Data Authenticity",
                            "type": "CWE"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-290",
                            "lang": "en",
                            "description": "CWE-290: Authentication Bypass by Spoofing",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "NONE",
                        "baseScore": 8.2,
                        "baseSeverity": "HIGH",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "LOW",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/honojs/hono/security/advisories/GHSA-xh87-mx6m-69f3",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/honojs/hono/security/advisories/GHSA-xh87-mx6m-69f3"
                },
                {
                    "name": "https://github.com/honojs/hono/commit/41adbf56e252c04611f8972364ac0887ae07a4c7",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/honojs/hono/commit/41adbf56e252c04611f8972364ac0887ae07a4c7"
                },
                {
                    "name": "https://github.com/honojs/hono/releases/tag/v4.12.2",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/honojs/hono/releases/tag/v4.12.2"
                }
            ],
            "affected": [
                {
                    "vendor": "honojs",
                    "product": "hono",
                    "versions": [
                        {
                            "version": ">= 4.12.0, < 4.12.2",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-02-25T15:01:44.681Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Hono is a Web application framework that provides support for any JavaScript runtime. In versions 4.12.0 and 4.12.1, when using the AWS Lambda adapter (`hono/aws-lambda`) behind an Application Load Balancer (ALB), the `getConnInfo()` function incorrectly selected the first value from the `X-Forwarded-For` header. Because AWS ALB appends the real client IP address to the end of the `X-Forwarded-For` header, the first value can be attacker-controlled. This could allow IP-based access control mechanisms (such as the `ipRestriction` middleware) to be bypassed. Version 4.12.2 patches the issue."
                }
            ],
            "source": {
                "advisory": "GHSA-xh87-mx6m-69f3",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-02-27T17:01:17.956003Z",
                                "id": "CVE-2026-27700",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "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": "2026-02-27T17:01:28.403Z"
                }
            }
        ]
    }
}