4.8Medium

CVE-2026-67617

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.

What this means for your business

  • An attacker can use it remotely, over a network, with an administrator login, but only after tricking someone into an action such as opening a file or a link.
  • FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 5% of all known flaws.

What to do

  1. 1Ask your IT team or provider whether any of your systems use the affected product.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

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Scoring

CVSS
4.8 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
CVSS v4
4.8
Weakness
CWE-79
Assigned by
disclosure@vulncheck.com

Dates

Published
2026-08-03
Last modified
2026-09-10
Sources
NVD

References

CVE-2026-67617 | CyberBrief