{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-73420",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-08-12T14:32:11.795Z",
        "datePublished": "2026-08-13T22:04:15.414Z",
        "dateUpdated": "2026-08-14T15:06:00.594Z"
    },
    "containers": {
        "cna": {
            "title": "NextAuth.js: Email normalizer validates the address before Unicode normalization, allowing a homoglyph @ bypass",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-180",
                            "lang": "en",
                            "description": "CWE-180: Incorrect Behavior Order: Validate Before Canonicalize",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "HIGH",
                        "vulnIntegrityImpact": "HIGH",
                        "vulnAvailabilityImpact": "NONE",
                        "subConfidentialityImpact": "NONE",
                        "subIntegrityImpact": "NONE",
                        "subAvailabilityImpact": "NONE",
                        "baseScore": 9.1,
                        "baseSeverity": "CRITICAL",
                        "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
                        "version": "4.0"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/nextauthjs/next-auth/security/advisories/GHSA-7rqj-j65f-68wh",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/nextauthjs/next-auth/security/advisories/GHSA-7rqj-j65f-68wh"
                },
                {
                    "name": "https://github.com/nextauthjs/next-auth/commit/19d2feb24359fa8c79418907fc68d9ec8152ca94",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/nextauthjs/next-auth/commit/19d2feb24359fa8c79418907fc68d9ec8152ca94"
                },
                {
                    "name": "https://github.com/nextauthjs/next-auth/commit/a63eee12a1a20cb35209e44195b097868517b9a0",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/nextauthjs/next-auth/commit/a63eee12a1a20cb35209e44195b097868517b9a0"
                },
                {
                    "name": "https://github.com/nextauthjs/next-auth/releases/tag/@auth/core@0.41.3",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/nextauthjs/next-auth/releases/tag/@auth/core@0.41.3"
                },
                {
                    "name": "https://github.com/nextauthjs/next-auth/releases/tag/next-auth@4.24.15",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/nextauthjs/next-auth/releases/tag/next-auth@4.24.15"
                },
                {
                    "name": "https://github.com/nextauthjs/next-auth/releases/tag/next-auth@5.0.0-beta.32",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/nextauthjs/next-auth/releases/tag/next-auth@5.0.0-beta.32"
                }
            ],
            "affected": [
                {
                    "vendor": "nextauthjs",
                    "product": "next-auth",
                    "versions": [
                        {
                            "version": "< 4.24.15",
                            "status": "affected"
                        },
                        {
                            "version": ">= 5.0.0-beta.4, < 5.0.0-beta.32",
                            "status": "affected"
                        }
                    ]
                },
                {
                    "vendor": "@auth",
                    "product": "core",
                    "versions": [
                        {
                            "version": ">= 0.1.0, < 0.41.3",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-08-13T22:04:15.414Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "NextAuth.js provides authentication for Next.js. Prior to @auth/core 0.41.3 and next-auth 4.24.15 and 5.0.0-beta.32, the defaultNormalizer used by the email and magic-link sign-in flow validates an address before applying Unicode normalization. An address can contain a Unicode character such as U+FF20 FULLWIDTH COMMERCIAL AT that is not ASCII at-sign but canonicalizes to an ASCII at-sign under NFKC or NFKD normalization. The address passes the normalizer's single-at-sign check, but a downstream sendVerificationRequest mail library or delivery service that normalizes the address can then see two at-sign separators and deliver the passwordless sign-in link to an attacker-controlled recipient. Applications are affected when the email provider uses the built-in normalizer rather than a custom normalizeIdentifier and the downstream sender applies Unicode normalization. An attacker who knows a victim's email address can request the misrouted magic link and sign in as the victim without victim interaction. This issue is fixed in @auth/core 0.41.3 and next-auth 4.24.15 and 5.0.0-beta.32."
                }
            ],
            "source": {
                "advisory": "GHSA-7rqj-j65f-68wh",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-08-14T15:05:10.354847Z",
                                "id": "CVE-2026-73420",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "Automatable": "yes"
                                    },
                                    {
                                        "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": "2026-08-14T15:06:00.594Z"
                }
            }
        ]
    }
}