Description
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.
References2
Metrics
- CVSS 3.1
-
4.8
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N - CVSS 4.0
-
4.8
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 20 · as of 13 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.