{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-73495",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-08-12T19:00:33.735Z",
        "datePublished": "2026-08-12T21:11:55.180Z",
        "dateUpdated": "2026-08-13T13:04:05.574Z"
    },
    "containers": {
        "cna": {
            "title": "blaze: Chunked-body trailer fields promoted into Request.headers in blaze-server (front-end header-sanitization bypass)",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-444",
                            "lang": "en",
                            "description": "CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "HIGH",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "NONE",
                        "baseScore": 7.4,
                        "baseSeverity": "HIGH",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/http4s/blaze/security/advisories/GHSA-46q4-43ph-c6fr",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/http4s/blaze/security/advisories/GHSA-46q4-43ph-c6fr"
                },
                {
                    "name": "https://github.com/http4s/blaze/commit/ef3e666c146cfc16cb6603f1fc3c464daab4a24f",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/http4s/blaze/commit/ef3e666c146cfc16cb6603f1fc3c464daab4a24f"
                },
                {
                    "name": "https://github.com/http4s/blaze/releases/tag/v0.23.18",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/http4s/blaze/releases/tag/v0.23.18"
                },
                {
                    "name": "https://github.com/http4s/blaze/releases/tag/v1.0.0-M42",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/http4s/blaze/releases/tag/v1.0.0-M42"
                }
            ],
            "affected": [
                {
                    "vendor": "http4s",
                    "product": "blaze",
                    "versions": [
                        {
                            "version": "< 0.23.18",
                            "status": "affected"
                        },
                        {
                            "version": ">= 1.0.0-M1, < 1.0.0-M42",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-08-12T21:11:55.180Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "blaze is a Scala library for building asynchronous pipelines, with a focus on network IO. Prior to 0.23.18 and 1.0.0-M42, blaze-server can merge HTTP/1.1 chunked-body trailer fields into Request.headers. Because trailer fields are attacker-controlled, an unauthenticated remote client can inject arbitrary header names and values, including X-Forwarded-For and internal authorization headers, that a fronting proxy sanitized from the request-header section, bypassing header-based trust decisions in the application. Any http4s application using BlazeServerBuilder over HTTP/1.1 whose routes or middleware trust proxy-set headers, including X-Forwarded-For, X-Real-IP, and X-Forwarded-Host, is affected. If a fronting proxy strips or normalizes those headers but forwards chunked bodies with trailers intact, an attacker can spoof client IP for allow-lists, rate limits, or auditing, forge the https scheme, or inject internal authorization headers. A promoted Connection: close trailer is also honored, allowing attacker-controlled termination of pooled backend connections. This issue is fixed in versions 0.23.18 and 1.0.0-M42."
                }
            ],
            "source": {
                "advisory": "GHSA-46q4-43ph-c6fr",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-08-13T13:02:55.958244Z",
                                "id": "CVE-2026-73495",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "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": "2026-08-13T13:04:05.574Z"
                }
            }
        ]
    }
}