CVE-2026-109303

Parse Server before 8.6.93 and 9.0.0 before 9.10.1-alpha.13 does not enforce identity-scoped protectedFields (authenticated, role, or per-user groups) on count queries using the $relatedTo operator, exposing the size of protected Relation fields. An authenticated user who can read the owning object can combine counts with an objectId constraint as a membership oracle to reveal confidential memberships such as private groups or block lists.

CVSS v3 4.3 MEDIUM

4.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/parse-community/parse-server/security/advisories/GHSA-rmhf-xv62-rm99
https://www.vulncheck.com/advisories/parse-server-before-8.6.93-and-9.0.0-before-9.10.1-alpha.13-protectedfields-bypass-via-relation-count-query

Configurations

No configuration.

History

12 Oct 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-12 17:17

Updated : 2026-10-13 20:39

NVD link : CVE-2026-109303

Mitre link : CVE-2026-109303

CVE.ORG link : CVE-2026-109303

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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