XSS in Masacms
CVE-2025-66492
Masa CMS is an open source Enterprise Content Management platform. Versions 7.2.8 and below, 7.3.1 through 7.3.13, 7.4.0-alpha.1 through 7.4.8 and 7.5.0 through 7.5.1 are vulnerable to XSS when an unsanitized value of the ajax URL query parameter is directly included within the <head> section of the HTML page. An attacker can execute arbitrary scripts in the context of the user's session, potentially leading to Session Hijacking, Data Theft, Defacement and Malware Distribution. This issue is fixed in versions 7.5.2, 7.4.9, 7.3.14, and 7.2.9. To work around this issue, configure a Web Application Firewall (WAF) rule (e.g., ModSecurity) to block requests containing common XSS payload characters in the ajax query parameter. Alternatively, implement server-side sanitization using middleware to strip or escape dangerous characters from the ajax parameter before it reaches the vulnerable rendering logic.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (14.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 14.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.000
Affected products
- Masacms — versions < 7.2.9, >= 7.3.1, < 7.3.14, >= 7.4.0-alpha.1, < 7.4.8
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2025-66492?
- CVE-2025-66492 is a high-severity vulnerability in Masacms, classified under Cross-site Scripting. CVSS score: 8.2/10. Published 2025-12-12.
- How severe is CVE-2025-66492?
- High severity. CVSS v3 base score is 8.2 out of 10.