{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "1.7.0-rc.2"
              },
              {
                "fixed": "1.7.3"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "DESCRIPTION"
            ]
          },
          "events": [
            {
              "introduced": "cc708e51bcb1d4c367d2bc6182e6fd7fd722ece8"
            },
            {
              "fixed": "597d39cb4aaaac1ad729051fbdd22a63b8ba8d8d"
            }
          ],
          "repo": "https://github.com/better-auth/better-auth",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-mx9r-x6ww-qjw9"
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-287"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/110xxx/CVE-2026-110863.json"
  },
  "details": "Better Auth @better-auth/sso from 1.7.0-rc.2 before 1.7.3 contains an authentication bypass vulnerability that allows authenticated users to sign in as other users by registering a personal SSO provider. Attackers can copy a legitimate provider's OIDC issuer or SAML entity ID and assert a victim's subject or NameID, because account lookup ignores providerId, creating sessions for victim accounts.",
  "id": "CVE-2026-110863",
  "modified": "2026-10-16T02:31:05.696591328Z",
  "published": "2026-10-14T22:52:50.378Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/110xxx/CVE-2026-110863.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/better-auth/better-auth/security/advisories/GHSA-mx9r-x6ww-qjw9"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-110863"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/better-auth-better-auth-sso-before-1.7.3-authentication-bypass-via-personal-sso-providers"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Better Auth @better-auth/sso before 1.7.3 Authentication Bypass via Personal SSO Providers"
}