{"id":"GHSA-6r2j-cxgf-495f","summary":"Parse Server vulnerable to session token exfiltration via `redirectClassNameForKey` query parameter","details":"### Impact\n\nA vulnerability in Parse Server's query handling allows an authenticated or unauthenticated attacker to exfiltrate session tokens of other users by exploiting the `redirectClassNameForKey` query parameter. Exfiltrated session tokens can be used to take over user accounts.\n\nThe vulnerability requires the attacker to be able to create or update an object with a new relation field, which depends on the Class-Level Permissions of at least one class.\n\n### Patches\n\nThe fix applies the same security checks that normally protect class access after the query redirect, ensuring that queries redirected via `redirectClassNameForKey` are subject to the same restrictions as direct queries to the target class.\n\n### Workarounds\n\nSet restrictive Class-Level Permissions to prevent clients from creating new fields on classes, specifically by disabling `addField` for public access and unauthenticated users. Note that this limits client functionality and does not fully eliminate the risk if a relation field pointing to a protected class already exists in the schema.\n\n### References\n\n- GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-6r2j-cxgf-495f\n- Fix Parse Server 9: https://github.com/parse-community/parse-server/releases/tag/9.5.2-alpha.8\n- Fix Parse Server 8: https://github.com/parse-community/parse-server/releases/tag/8.6.21","aliases":["BIT-parse-2026-30965","CVE-2026-30965"],"modified":"2026-03-14T03:41:04.557395Z","published":"2026-03-11T00:20:38Z","database_specific":{"github_reviewed":true,"github_reviewed_at":"2026-03-11T00:20:38Z","nvd_published_at":"2026-03-10T21:16:48Z","cwe_ids":["CWE-863"],"severity":"CRITICAL"},"references":[{"type":"WEB","url":"https://github.com/parse-community/parse-server/security/advisories/GHSA-6r2j-cxgf-495f"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-30965"},{"type":"PACKAGE","url":"https://github.com/parse-community/parse-server"},{"type":"WEB","url":"https://github.com/parse-community/parse-server/releases/tag/8.6.21"},{"type":"WEB","url":"https://github.com/parse-community/parse-server/releases/tag/9.5.2-alpha.8"}],"affected":[{"package":{"name":"parse-server","ecosystem":"npm","purl":"pkg:npm/parse-server"},"ranges":[{"type":"SEMVER","events":[{"introduced":"9.0.0-alpha.1"},{"fixed":"9.5.2-alpha.8"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-6r2j-cxgf-495f/GHSA-6r2j-cxgf-495f.json"}},{"package":{"name":"parse-server","ecosystem":"npm","purl":"pkg:npm/parse-server"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"8.6.21"}]}],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/03/GHSA-6r2j-cxgf-495f/GHSA-6r2j-cxgf-495f.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N"}]}