CVE-2026-33042: Parse Server affected by empty authData bypassing credential requirement on signup

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-03-18 · updated 2026-06-17
Weakness: CWE-287

Description

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.

Affected products

parse-community parse-server: before 8.6.49; from 9.0.0 before 9.6.0; 9.6.0-alpha1, 9.6.0-alpha10, 9.6.0-alpha11, 9.6.0-alpha12, 9.6.0-alpha13, 9.6.0-alpha14 (+22) — fixed in 8.6.49, 9.6.0

How to fix

Upgrade to a fixed version: parse-community parse-server 8.6.49, 9.6.0. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2026-33042 or the next vulnerability affects your stack