CVE-2026-3395 Details.
MaxSite CMS <=109.1 - Remote Code Execution
Atlas does not check this one. Needs requests that change data.
To test for this one, the check would have to send requests that could change data on the site. Atlas only ever reads public pages, so it does not run this check.
About CVE-2026-3395. What It Means.
MaxSite CMS through 109.1 allows unauthenticated remote attackers to execute arbitrary code via the MarkItUp editor preview AJAX endpoint, preview-ajax.php. The endpoint insufficiently authenticates the request, failing to ensure the user is logged in, and processes the attacker's input via unsafe usage of PHP eval() on user-supplied [php]...[/php] shortcodes. By providing a POST request to the vulnerable /ajax/ endpoint with crafted input, attackers may achieve remote code…
Affected Product. What Is Hit.
- Vendor
- max-3000
- Product
- MAX-3000 MaxSite CMS
References. Where To Read More.
- https://github.com/mbanyamer/CVE-2026-3395-MaxSite-CMS-Unauthenticated-RCE
- https://github.com/rootdirective-sec/CVE-2026-3395-Lab
- https://github.com/maxsite/cms/commit/08937a3c5d672a242d68f53e9fccf8a748820ef3
- https://vuldb.com/?id.348281
- https://www.cyber.gov.au/about-us/view-all-content/alerts-and-advisories/large-scale-exploitation-campaign-targeting-website-content-management-systems-cms
- https://nvd.nist.gov/vuln/detail/CVE-2026-3395
FAQ
Common Questions.
MaxSite CMS <=109.1 - Remote Code Execution. MaxSite CMS through 109.1 allows unauthenticated remote attackers to execute arbitrary code via the MarkItUp editor preview AJAX endpoint, preview-ajax.php. The endpoint insufficiently authenticates the request, failing to ensure the user is logged in, and processes the attacker's input via unsafe usage of PHP eval() on user-supplied [php]...[/php] shortcodes. By providing a POST request to the vulnerable /ajax/ endpoint with crafted input, attackers may achieve remote code…
No. To test for this one, the check would have to send requests that could change data on the site. Atlas only ever reads public pages, so it does not run this check. The facts about CVE-2026-3395 are on this page, and you can request a demo to see how Brandefense watches your whole external attack surface.
CVE-2026-3395 is not on the CISA Known Exploited Vulnerabilities list at the time of writing, but it is still worth fixing.
Update MAX-3000 MaxSite CMS to the latest version from the vendor, or follow the vendor's advice to switch off the affected feature. Vendor links are listed on this page when they are known.
This page lists the public facts about CVE-2026-3395. Atlas does not run a check for it, so nothing here says whether a particular site is affected.