CVE-2026-87928: Unrestricted Upload of File with Dangerous Type in MaxSite MaxSite CMS
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.
CVSS v4.0
Score 5.1medium
Affected software
MaxSite
MaxSite CMS
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-87928 is a cross-site scripting vulnerability in MaxSite CMS versions 0.94 through 109.6. The flaw exists in the admin_page upload handler, which does not restrict the upload of HTML files by logged-in users. Attackers can exploit this by uploading HTML files containing malicious scripts to the uploads/_pages/ directory. When these files are accessed by site visitors, the scripts execute in their browsers, resulting in persistent stored XSS attacks.
Potential Impact
An attacker with login access can upload malicious HTML files that execute arbitrary scripts in the browsers of visitors who access these files. This can lead to persistent stored cross-site scripting attacks, potentially compromising user sessions or performing unauthorized actions in the context of affected users.
Mitigation Recommendations
No patch or official fix information is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, restrict upload permissions to trusted users only and consider disabling HTML file uploads in the admin_page upload handler if possible.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-09-09T16:12:25.344Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6aa18eeaacd9273b499ae5cf
Added to database: 09/09/2026, 16:52:58 UTC
Last enriched: 09/26/2026, 03:26:17 UTC
Last updated: 10/12/2026, 18:48:24 UTC
Views: 63
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