{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-45364",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-05-12T00:51:29.085Z",
        "datePublished": "2026-05-28T21:34:51.446Z",
        "dateUpdated": "2026-05-29T19:05:38.845Z"
    },
    "containers": {
        "cna": {
            "title": "Better Auth: Rate limiter keys IPv6 addresses individually and is bypassable via prefix rotation",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-307",
                            "lang": "en",
                            "description": "CWE-307: Improper Restriction of Excessive Authentication Attempts",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "LOW",
                        "baseScore": 7.3,
                        "baseSeverity": "HIGH",
                        "confidentialityImpact": "LOW",
                        "integrityImpact": "LOW",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
                        "version": "3.1"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/better-auth/better-auth/security/advisories/GHSA-p6v2-xcpg-h6xw",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/better-auth/better-auth/security/advisories/GHSA-p6v2-xcpg-h6xw"
                },
                {
                    "name": "https://github.com/better-auth/better-auth/pull/7470",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/better-auth/better-auth/pull/7470"
                },
                {
                    "name": "https://github.com/better-auth/better-auth/pull/7509",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/better-auth/better-auth/pull/7509"
                },
                {
                    "name": "https://github.com/better-auth/better-auth/commit/43e719bcc0c223c7079fa0c611a9cf7ea1188254",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/better-auth/better-auth/commit/43e719bcc0c223c7079fa0c611a9cf7ea1188254"
                },
                {
                    "name": "https://github.com/better-auth/better-auth/commit/57af0f7b910dcf7b1a5c0615d10b9bd56bb69bef",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/better-auth/better-auth/commit/57af0f7b910dcf7b1a5c0615d10b9bd56bb69bef"
                }
            ],
            "affected": [
                {
                    "vendor": "better-auth",
                    "product": "better-auth",
                    "versions": [
                        {
                            "version": "< 1.4.17",
                            "status": "affected"
                        },
                        {
                            "version": ">= 1.5.0-beta.1, < 1.5.0-beta.9",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-05-28T21:34:51.446Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Better Auth is an authentication and authorization library for TypeScript. Prior to 1.4.17 and 1.5.0-beta.9, Better Auth's HTTP rate limiter keyed each request by the exact textual IP address it received in x-forwarded-for (or the configured IP-bearing header). IPv6 clients controlling a typical /64 allocation could rotate through 2^64 distinct source addresses without exhausting the per-address counter, defeating rate limiting on /sign-in/email, /sign-up/email, /forget-password, and every other path the limiter protects. The same bug allowed a single client to vary the textual encoding of one IPv6 address (uppercase, compression, IPv4-mapped, hex-encoded IPv4-in-IPv6) and produce multiple distinct keys. This vulnerability is fixed in 1.4.17 and 1.5.0-beta.9."
                }
            ],
            "source": {
                "advisory": "GHSA-p6v2-xcpg-h6xw",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-05-29T19:05:14.121201Z",
                                "id": "CVE-2026-45364",
                                "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": "2026-05-29T19:05:38.845Z"
                }
            }
        ]
    }
}