Parse Server allows attackers to find existing email addresses

Summary

If you use Parse Server with email verification enabled, an attacker can try different email addresses to figure out if they're already registered in your app. To fix this, update to Parse Server 9.6.0-alpha.8 or 8.6.34. Until then, keep an eye on your server logs and report any suspicious activity.

What to do

Update parse-server to version 9.6.0-alpha.8.
Update parse-server to version 8.6.34.

Affected software

Vendor	Product	Affected versions	Fix available
–	parse-server	> 9.0.0-alpha.1 , <= 9.6.0-alpha.8	9.6.0-alpha.8
–	parse-server	<= 8.6.34	8.6.34
parseplatform	parse-server	<= 8.6.34	–
parseplatform	parse-server	> 9.0.0 , <= 9.6.0	–
parseplatform	parse-server	9.6.0	–
parseplatform	parse-server	9.6.0	–
parseplatform	parse-server	9.6.0	–
parseplatform	parse-server	9.6.0	–
parseplatform	parse-server	9.6.0	–
parseplatform	parse-server	9.6.0	–
parseplatform	parse-server	9.6.0	–

Original title

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 8.6.34 and 9.6.0-alpha.8, the email verification endpoint (/verificationEmailRequest...

Original description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 8.6.34 and 9.6.0-alpha.8, the email verification endpoint (/verificationEmailRequest) returns distinct error responses depending on whether an email address belongs to an existing user, is already verified, or does not exist. An attacker can send requests with different email addresses and observe the error codes to determine which email addresses are registered in the application. This is a user enumeration vulnerability that affects any Parse Server deployment with email verification enabled (verifyUserEmails: true). This vulnerability is fixed in 8.6.34 and 9.6.0-alpha.8.

ghsa CVSS4.0 6.3

Vulnerability type

CWE-204