{"id":"BIT-parse-2026-27804","summary":"Parse Server: Account takeover via JWT algorithm confusion in Google auth adapter","details":"Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.3 and 9.3.1, an unauthenticated attacker can forge a Google authentication token with `alg: \"none\"` to log in as any user linked to a Google account, without knowing their credentials. All deployments with Google authentication enabled are affected. The fix in versions 8.6.3 and 9.3.1 hardcodes the expected `RS256` algorithm instead of trusting the JWT header, and replaces the Google adapter's custom key fetcher with `jwks-rsa` which rejects unknown key IDs. As a workaround, dsable Google authentication until upgrading is possible.","aliases":["CVE-2026-27804","GHSA-4q3h-vp4r-prv2"],"modified":"2026-03-13T10:40:19.206039Z","published":"2026-03-02T11:46:50.810Z","database_specific":{"severity":"Critical","cpes":["cpe:2.3:a:parseplatform:parse-server:*:*:*:*:*:node.js:*:*"]},"references":[{"type":"WEB","url":"https://github.com/parse-community/parse-server/commit/9b94083accb7f3e72c6b8126c195c7a03dd2dfd7"},{"type":"WEB","url":"https://github.com/parse-community/parse-server/commit/9d5942d50e55c822924c27b05aa98f1393e7a330"},{"type":"WEB","url":"https://github.com/parse-community/parse-server/releases/tag/8.6.3"},{"type":"WEB","url":"https://github.com/parse-community/parse-server/releases/tag/9.3.1-alpha.4"},{"type":"WEB","url":"https://github.com/parse-community/parse-server/security/advisories/GHSA-4q3h-vp4r-prv2"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-27804"}],"affected":[{"package":{"name":"parse","ecosystem":"Bitnami","purl":"pkg:bitnami/parse"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"8.6.3"},{"introduced":"9.0.0"},{"fixed":"9.3.1"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/parse/BIT-parse-2026-27804.json"},"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:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}],"schema_version":"1.7.5"}