{"id":"CVE-2026-30967","aliases":["BIT-parse-2026-30967","GHSA-fr88-w35c-r596"],"url":"https://o3.security/vulnerability/CVE-2026-30967","summary":"Parse Server OAuth2 authentication adapter account takeover via identity spoofing","details":"### Impact\n\nThe OAuth2 authentication adapter, when configured without the `useridField` option, only verifies that a token is active via the provider's token introspection endpoint, but does not verify that the token belongs to the user identified by `authData.id`. An attacker with any valid OAuth2 token from the same provider can authenticate as any other user.\n\nThis affects any Parse Server deployment that uses the generic OAuth2 authentication adapter (configured with `oauth2: true`) without setting the `useridField` option.\n\n### Patches\n\nThe vulnerability is fixed by defaulting `useridField` to `sub`, which is the standard subject identifier field defined by [RFC 7662](https://datatracker.ietf.org/doc/html/rfc7662). The adapter now always validates the token's identity against the claimed user ID, even when `useridField` is not explicitly configured.\n\n### Workarounds\n\nSet the `useridField` option to the appropriate field name for your OAuth2 provider (e.g. `sub`) in the Parse Server authentication configuration.\n\n### References\n\n- GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-fr88-w35c-r596\n- Fix Parse Server 9: https://github.com/parse-community/parse-server/releases/tag/9.5.2-alpha.9\n- Fix Parse Server 8: https://github.com/parse-community/parse-server/releases/tag/8.6.22","published":"2026-03-10T20:46:40.222Z","modified":"2026-08-12T03:51:19.949786113Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"parse-server","fixedVersion":"9.5.2-alpha.9"},{"ecosystem":"npm","name":"parse-server","fixedVersion":"8.6.22"}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/parse-community/parse-server/releases/tag/8.6.22"},{"type":"WEB","url":"https://github.com/parse-community/parse-server/releases/tag/9.5.2-alpha.9"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/30xxx/CVE-2026-30967.json"},{"type":"ADVISORY","url":"https://github.com/parse-community/parse-server/security/advisories/GHSA-fr88-w35c-r596"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-30967"},{"type":"PACKAGE","url":"https://github.com/parse-community/parse-server"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:19.949786113Z"}}