6.3
MEDIUM CVSS 4.0
CVE-2026-66009
Parse Server 9.0.0 Information Disclosure via GraphQL Error Messages
Description

Parse Server versions >= 9.0.0 before 9.10.0-alpha.5 and >= 8.2.2 before 8.6.86 return GraphQL validation error messages that name required custom input fields even when public introspection is disabled (graphQLPublicIntrospection: false, the default). A client holding only the public application id — with no user session, master key, or maintenance key — can trigger validation errors to learn the names of required (non-null) custom fields on classes it already references by name, partially defeating the schema-hiding intent of disabling public introspection. No stored data, credentials, optional field names, unreferenced class names, or Cloud Code function names are exposed.

INFO

Published Date :

July 24, 2026, 1:18 p.m.

Last Modified :

July 24, 2026, 1:18 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-66009 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 MEDIUM [email protected]
Solution
Update Parse Server to patch information disclosure vulnerability via GraphQL validation errors.
  • Update Parse Server to version 8.6.86 or 9.10.0-alpha.5.
  • Apply vendor-supplied patches if available.
  • Review GraphQL schema for sensitive information.
  • Limit public access to sensitive GraphQL endpoints.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-66009.

URL Resource
https://github.com/parse-community/parse-server/security/advisories/GHSA-2fgh-8j2g-w354
https://www.vulncheck.com/advisories/parse-server-information-disclosure-via-graphql-error-messages-2
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-66009 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-66009 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-66009 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-66009 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 24, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'parse-community', 'product': 'parse-server', 'versions': [{'status': 'affected', 'version': '9.0.0', 'lessThan': '9.10.0-alpha.5', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '9.10.0-alpha.5', 'versionType': 'semver'}], 'packageURL': 'pkg:npm/parse-server', 'defaultStatus': 'unaffected'}, {'vendor': 'parse-community', 'product': 'parse-server', 'versions': [{'status': 'affected', 'version': '8.2.2', 'lessThan': '8.6.86', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '8.6.86', 'versionType': 'semver'}], 'packageURL': 'pkg:npm/parse-server', 'defaultStatus': 'unaffected'}]
    Added Description Parse Server versions >= 9.0.0 before 9.10.0-alpha.5 and >= 8.2.2 before 8.6.86 return GraphQL validation error messages that name required custom input fields even when public introspection is disabled (graphQLPublicIntrospection: false, the default). A client holding only the public application id — with no user session, master key, or maintenance key — can trigger validation errors to learn the names of required (non-null) custom fields on classes it already references by name, partially defeating the schema-hiding intent of disabling public introspection. No stored data, credentials, optional field names, unreferenced class names, or Cloud Code function names are exposed.
    Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-209
    Added Reference https://github.com/parse-community/parse-server/security/advisories/GHSA-2fgh-8j2g-w354
    Added Reference https://www.vulncheck.com/advisories/parse-server-information-disclosure-via-graphql-error-messages-2
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.