parse-community parse-server up to 8.6.79/9.9.1-alpha.5 Private Group relatedTo authorization

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k3.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in parse-community parse-server up to 8.6.79/9.9.1-alpha.5. Impacted is an unknown function of the component Private Group Handler. Executing a manipulation of the argument relatedTo can lead to authorization. This vulnerability is tracked as CVE-2026-53726. The attack can be launched remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in parse-community parse-server up to 8.6.79/9.9.1-alpha.5. It has been declared as problematic. This vulnerability affects an unknown functionality of the component Private Group Handler. The manipulation of the argument relatedTo with an unknown input leads to a authorization vulnerability. The CWE definition for the vulnerability is CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. As an impact it is known to affect confidentiality. CVE summarizes:

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to versions 8.6.80 and 9.9.1-alpha.6, a relation query using the $relatedTo operator could read the membership of a Relation field even when that field was hidden from the requesting client by protectedFields, and even when the object owning the relation was not readable by the client under its ACL or class-level permissions. The request requires only the public API credentials that Parse clients normally carry — no user session, master key, or Cloud Code is needed. As a result, an unauthenticated client who knows or obtains the owning object's objectId could enumerate the objects linked through a protected relation, or combine the operator with an objectId constraint to use it as a membership oracle — confirming whether a specific object is linked to a private parent. This affects applications that rely on protectedFields or object ACLs to keep Relation membership confidential, such as private group memberships, block lists, or account-to-resource associations. This issue has been patched in versions 8.6.80 and 9.9.1-alpha.6.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-53726 since 06/10/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available.

Upgrading to version 8.6.80 or 9.9.1-alpha.6 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-639 / CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: parse-server 8.6.80/9.9.1-alpha.6
Patch: github.com

Timelineinfo

06/10/2026 CVE reserved
06/12/2026 +2 days Advisory disclosed
06/12/2026 +0 days VulDB entry created
06/12/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-wmwx-jr2p-4j4r
Status: Confirmed

CVE: CVE-2026-53726 (🔒)
GCVE (CVE): GCVE-0-2026-53726
GCVE (VulDB): GCVE-100-370672

Entryinfo

Created: 06/12/2026 22:26
Changes: 06/12/2026 22:26 (69)
Complete: 🔍
Cache ID: 216::103

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