---
id: CVE-2026-89145
title: >-
  Flextype CMS versions 0.9.9 through 1.0.0-alpha.3 fail to HTML-escape plugin
  directory names in the dependency error page rendered by
  getValidPluginsDependencies()
summary: >-
  Flextype CMS versions 0.9.9 through 1.0.0-alpha.3 fail to HTML-escape plugin
  directory names in the dependency error page rendered by
  getValidPluginsDependencies(). Attackers with write access to the plugins
  directory can create a plugin…
severity: medium
cvss: 4.2
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N'
cwe:
  - CWE-79
vendor: flextype
product: flextype
affected:
  - flextype >= 0.9.9 <= 1.0.0-alpha.3
published: '2026-09-11'
updated: '2026-09-11'
sourceUpdated: '2026-09-11T15:17:08.727'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-89145'
references:
  - url: 'https://github.com/flextype/flextype'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/flextype/flextype/blob/aea4ead8c449ea5517ed53b6dcbd28b0a528ad9d/src/flextype/core/Plugins.php#L345
    label: disclosure@vulncheck.com
  - url: 'https://github.com/flextype/flextype/issues/597'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/flextype-cms-0.9.9-through-1.0.0-alpha.3-stored-xss-via-plugin-directory
    label: disclosure@vulncheck.com
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-11T14:24:34.386841Z'
epss: 0.00128
epssPercentile: 0.02819
ingestedAt: '2026-09-11T16:45:47.859Z'
---

## Overview

Flextype CMS versions 0.9.9 through 1.0.0-alpha.3 fail to HTML-escape plugin directory names in the dependency error page rendered by getValidPluginsDependencies(). Attackers with write access to the plugins directory can create a plugin with HTML characters in its name to execute arbitrary scripts in users' browsers when dependency validation fails.

## Remediation

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