---
id: CVE-2026-67617
title: >-
  Microweber CMS through 2.0.20 contains a stored cross-site scripting
  vulnerability in the content tagging system that allows admin-authenticated
  attackers to inject arbitrary JavaScript by submitting malicious payloads via
  the tag_names …
summary: >-
  Microweber CMS through 2.0.20 contains a stored cross-site scripting
  vulnerability in the content tagging system that allows admin-authenticated
  attackers to inject arbitrary JavaScript by submitting malicious payloads via
  the tag_names …
severity: medium
cvss: 4.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N'
cwe:
  - CWE-79
published: '2026-08-03'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T20:44:57.447'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-67617'
references:
  - url: 'https://github.com/theopaid/Stored-XSS-via-Content-Tag-Names-Microweber-'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/microweber-cms-stored-xss-via-tag-names-parameter
    label: disclosure@vulncheck.com
tags:
  - nvd
epss: 0.00273
epssPercentile: 0.1757
ingestedAt: '2026-09-10T21:05:53.593Z'
---

## Overview

Microweber CMS through 2.0.20 contains a stored cross-site scripting vulnerability in the content tagging system that allows admin-authenticated attackers to inject arbitrary JavaScript by submitting malicious payloads via the tag_names parameter of the GET /api/save_content_admin endpoint, bypassing three independent sanitization controls including XSS middleware that ignores GET requests, a strip_unsafe() function that only matches double-quoted onerror attributes, and a titlecase normalizer that passes HTML decimal entity-encoded payloads through unchanged. Attackers can store malicious scripts that execute without user interaction for every visitor to the public blog page and within the admin post editor, enabling session riding through same-origin fetch requests using the CSRF token embedded in the page.

## Remediation

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