{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-81509",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-08-26T20:58:58.084Z",
        "datePublished": "2026-10-26T17:19:15.467Z",
        "dateUpdated": "2026-10-26T19:34:58.155Z"
    },
    "containers": {
        "cna": {
            "title": "nforwardauth: Unvalidated r parameter allows post-authentication open redirect",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-601",
                            "lang": "en",
                            "description": "CWE-601: URL Redirection to Untrusted Site ('Open Redirect')",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "NONE",
                        "baseScore": 6.1,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "LOW",
                        "integrityImpact": "LOW",
                        "privilegesRequired": "NONE",
                        "scope": "CHANGED",
                        "userInteraction": "REQUIRED",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/nosduco/nforwardauth/security/advisories/GHSA-q64r-v7j5-6hfg",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/nosduco/nforwardauth/security/advisories/GHSA-q64r-v7j5-6hfg"
                },
                {
                    "name": "https://github.com/nosduco/nforwardauth/pull/71",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/nosduco/nforwardauth/pull/71"
                },
                {
                    "name": "https://github.com/nosduco/nforwardauth/commit/664f2602f9e1459558d1c4c55019f6d48bc64c43",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/nosduco/nforwardauth/commit/664f2602f9e1459558d1c4c55019f6d48bc64c43"
                },
                {
                    "name": "https://github.com/nosduco/nforwardauth/releases/tag/v1.5.1",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/nosduco/nforwardauth/releases/tag/v1.5.1"
                }
            ],
            "affected": [
                {
                    "vendor": "nosduco",
                    "product": "nforwardauth",
                    "versions": [
                        {
                            "version": "< 1.5.1",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-10-26T18:12:30.433Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "nforwardauth is a forward auth service that allows the use of a single authentication middleware for multiple sites. Versions prior to 1.5.1 accept an unvalidated `r` query parameter on the `/login` endpoint and use them as the post-authentication redirect destination. An unauthenticated attacker can create a legitimate `nforwardauth` login URL that redirects a victim to an attacker-controlled website after the victim successfully authenticates. This issue may facilitate phishing and other social-engineering attacks by abusing the trust associated with the legitimate authentication domain. This vulnerability does not provide an unauthenticated ForwardAuth bypass. Version 1.5.1 contains a patch."
                }
            ],
            "source": {
                "advisory": "GHSA-q64r-v7j5-6hfg",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-10-26T19:29:40.719883Z",
                                "id": "CVE-2026-81509",
                                "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": "2026-10-26T19:34:58.155Z"
                }
            }
        ]
    }
}