Description
MaxSite CMS versions 0.94 through 109.6 contain a cross-site scripting vulnerability in the admin_page upload handler that allows any logged-in user to upload HTML files. Attackers can upload HTML containing malicious scripts to the uploads/_pages/ directory, which executes in visitors' browsers when the file is accessed, enabling persistent stored cross-site scripting attacks.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| MaxSite | MaxSite CMS | 0.94 – ≤ 109.6 | — |
References
- https://github.com/maxsite/cms product
- https://github.com/EviL0rd/maxsite-cve2/blob/main/2026.09.08-maxsite-cms-arbitrary-file-write-stored-xss.md exploit technical-description
- https://github.com/maxsite/cms/blob/2ca0a0c7d1d71106a25dbb0f2aedaaefbf12802c/application/maxsite/admin/plugins/admin_page/uploads-require-maxsite.php#L1-L64 technical-description
- VulnCheck Advisory: MaxSite CMS 0.94 through 109.6 HTML Upload XSS via admin_page third-party-advisory