CVE-2026-33042: Parse Server affected by empty authData bypassing credential requirement on signup
Impact
A user can sign up without providing credentials by sending an empty authData object, bypassing the username and password requirement. This allows the creation of authenticated sessions without proper credentials, even when anonymous users are disabled.
Patches
The fix ensures that empty or non-actionable authData is treated the same as absent authData for the purpose of credential validation on new user creation. Username and password are now required when no valid auth provider data is present.
Workarounds
Use a Cloud Code beforeSave trigger on the User class to reject signups where authData is empty and no username/password is provided.
Other sources
Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.6.0-alpha.29 and 8.6.49, a user can sign up without providing credentials by sending an empty authData object, bypassing the username and password requirement. This allows the creation of authenticated sessions without proper credentials, even when anonymous users are disabled. The fix in 9.6.0-alpha.29 and 8.6.49 ensures that empty or non-actionable authData is treated the same as absent authData for the purpose of credential validation on new user creation. Username and password are now required when no valid auth provider data is present. As a workaround, use a Cloud Code beforeSave trigger on the User class to reject signups where authData is empty and no username/password is provided.
— MITRE
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-33042?
CVE-2026-33042 has a high severity as it allows users to bypass authentication completely.
How do I fix CVE-2026-33042?
To fix CVE-2026-33042, upgrade to parse-server version 8.6.49 or version 9.6.0-alpha.29.
Who is affected by CVE-2026-33042?
The vulnerability impacts installations of parse-server prior to version 8.6.49 and between 9.0.0 and 9.6.0-alpha.29.
What are the implications of CVE-2026-33042?
CVE-2026-33042 allows unauthorized users to create authenticated sessions, compromising user data security.
Is it possible to disable anonymous sign-ups to mitigate CVE-2026-33042?
Disabling anonymous sign-ups will not mitigate CVE-2026-33042, as the vulnerability allows bypassing such restrictions.