---
id: CVE-2026-113659
title: >-
  ApostropheCMS: Client-side Prototype Pollution in apos.http.parseQuery leading
  to DOM-based XSS against authenticated users
summary: >-
  ApostropheCMS is an open-source Node.js content management system. Prior to
  4.33.0, an unauthenticated attacker can send a crafted link whose query string
  is automatically parsed by apos.http.parseQuery when an authenticated victim
  loads…
severity: medium
cvss: 6.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'
cvssSource: cna
cwe:
  - CWE-79
  - CWE-1321
vendor: apostrophecms
product: apostrophe
affected:
  - apostrophe < 4.33.0
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-28T13:59:41.334411Z'
published: '2026-10-20'
updated: '2026-10-28'
sourceUpdated: '2026-10-28T13:59:49.929Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-113659'
references:
  - url: >-
      https://github.com/apostrophecms/apostrophe/security/advisories/GHSA-m2m5-rw3w-cwmj
    label: >-
      https://github.com/apostrophecms/apostrophe/security/advisories/GHSA-m2m5-rw3w-cwmj
  - url: >-
      https://github.com/apostrophecms/apostrophe/commit/9500b8b0e1d630d5e07fbb5fd2c25ed0943845ce
    label: >-
      https://github.com/apostrophecms/apostrophe/commit/9500b8b0e1d630d5e07fbb5fd2c25ed0943845ce
  - url: >-
      https://github.com/apostrophecms/apostrophe/commit/f84fd41cbf6c22eb8d0008fc9c25df1f7130b350
    label: >-
      https://github.com/apostrophecms/apostrophe/commit/f84fd41cbf6c22eb8d0008fc9c25df1f7130b350
  - url: 'https://github.com/apostrophecms/apostrophe/releases/tag/apostrophe@4.33.0'
    label: 'https://github.com/apostrophecms/apostrophe/releases/tag/apostrophe@4.33.0'
  - url: 'https://github.com/advisories/GHSA-m2m5-rw3w-cwmj'
tags:
  - cve.org
  - ghsa
  - npm
epss: 0.00345
epssPercentile: 0.27853
aliases:
  - GHSA-m2m5-rw3w-cwmj
ecosystem: npm
patched:
  - apostrophe 4.33.0
ingestedAt: '2026-10-20T18:14:37.225Z'
---

## Overview

ApostropheCMS is an open-source Node.js content management system. Prior to 4.33.0, an unauthenticated attacker can send a crafted link whose query string is automatically parsed by apos.http.parseQuery when an authenticated victim loads a page with the admin bundle. The parser accepts the special __proto__, constructor, and prototype path keys, allowing browser prototype mutation that can reach an unsafe DOM sink and execute script in the victim's session; anonymous visitors do not load the affected admin context. This issue is fixed in version 4.33.0.

## Affected

- `apostrophe < 4.33.0`

## Remediation

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

## Package advisory (CVE-2026-113659)

Affected packages:

- `apostrophe < 4.33.0`

Patched in:

- `apostrophe 4.33.0`

Source: https://github.com/advisories/GHSA-m2m5-rw3w-cwmj