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CVE-2026-66009
Published:July 24, 2026
Updated:August 04, 2026
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.
Affected Packages
https://github.com/parse-community/parse-server.git (GITHUB):
Affected version(s) >=9.0.0 <9.10.0-alpha.5
Fix Suggestion:
Update to version 9.10.0-alpha.5
https://github.com/parse-community/parse-server.git (GITHUB):
Affected version(s) >=8.2.2 <8.6.86
Fix Suggestion:
Update to version 8.6.86
parse-server (NPM):
Affected version(s) >=9.0.0 <9.10.0-alpha.5
Fix Suggestion:
Update to version 9.10.0-alpha.5
parse-server (NPM):
Affected version(s) >=8.2.2 <8.6.86
Fix Suggestion:
Update to version 8.6.86
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CVSS v4
Base Score:
6.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
PRESENT
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
LOW
Vulnerable System Integrity
NONE
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Weakness Type (CWE)
Generation of Error Message Containing Sensitive Information
EPSS
Base Score:
0.26