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 9.1.1-alpha.4, 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 9.1.1-alpha.4 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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
References 5
https://github.com/parse-community/parse-server/commit/9b94083accb7f3e72c6b8126…
security-advisories@github.com
https://github.com/parse-community/parse-server/commit/9d5942d50e55c822924c27b0…
security-advisories@github.com
https://github.com/parse-community/parse-server/releases/tag/8.6.3
security-advisories@github.com
https://github.com/parse-community/parse-server/releases/tag/9.3.1-alpha.4
security-advisories@github.com
https://github.com/parse-community/parse-server/security/advisories/GHSA-4q3h-v…
security-advisories@github.com