Auth bypass in Parse-Community Parse-Server

CVE-2026-30967

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.5.2-alpha.9. and 8.6.22, the OAuth2 authentication adapter, when configured without the useridField option, only verifies that a token is active via the provider's token introspection endpoint, but does not verify that the token belongs to the user identified by authData.id. An attacker with any valid OAuth2 token from the same provider can authenticate as any other user. This affects any Parse Server deployment that uses the generic OAuth2 authentication adapter (configured with oauth2: true) without setting the useridField option. This vulnerability is fixed in 9.5.2-alpha.9. and 8.6.22.

Vulnerability class: Broken Authentication

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.007 (50.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 50.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-30967: held from 0.003 to 0.007.

EPSS over last 30 days · oldest: 0.003 · newest: 0.007 · change: +0.003

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-30967?
CVE-2026-30967 is a high-severity vulnerability in Parse-Community Parse-Server, classified under Improper Authentication. CVSS score: 8.8/10. Published 2026-03-10.
How severe is CVE-2026-30967?
High severity. CVSS v3 base score is 8.8 out of 10.