---
id: CVE-2026-119569
title: Parse Server 9.0.0 before 9.10.5-alpha.9 Prototype Pollution Denial of Service
summary: >-
  Parse Server before 8.6.108 and 9.0.0 before 9.10.5-alpha.9 contains a
  prototype pollution vulnerability because user-controlled keys are expanded
  into objects without own-property checks. Clients with class write access can
  send dot not…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-1321
vendor: parse-community
product: parse-server
affected:
  - parse-server >= 9.0.0 < 9.10.5-alpha.9
  - parse-server < 8.6.108
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-30T15:21:11.278620Z'
published: '2026-10-30'
updated: '2026-10-30'
sourceUpdated: '2026-10-30T15:53:54.963Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-119569'
references:
  - url: >-
      https://github.com/parse-community/parse-server/security/advisories/GHSA-rx55-fw4j-pvpx
    label: GitHub Security Advisory (GHSA-rx55-fw4j-pvpx)
  - url: >-
      https://www.vulncheck.com/advisories/parse-server-9.0.0-before-9.10.5-alpha.9-prototype-pollution-denial-of-service
    label: >-
      VulnCheck Advisory: Parse Server 9.0.0 before 9.10.5-alpha.9 Prototype
      Pollution Denial of Service
tags:
  - cve.org
epss: 0.00378
epssPercentile: 0.3195
ingestedAt: '2026-11-05T16:07:30.519Z'
---

## Overview

Parse Server before 8.6.108 and 9.0.0 before 9.10.5-alpha.9 contains a prototype pollution vulnerability because user-controlled keys are expanded into objects without own-property checks. Clients with class write access can send dot notation field keys or ACL entry names matching built-in object members to corrupt built-in functions, causing all requests to fail until server restart.

## Affected

- `parse-server >= 9.0.0 < 9.10.5-alpha.9`
- `parse-server < 8.6.108`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.