Which products and versions are affected by CVE-2026-3395?

Affected: Maxsite CMS (Max-3000) versions >= 109.0. The full list is in the CVE brief.

Is CVE-2026-3395 being exploited in the wild?

It is exploited in the wild, listed in Industry KEV feed since Jul 9, 2026.

Is CVE-2026-3395 in the CISA KEV catalog?

No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.

Is there a public exploit for CVE-2026-3395?

Public exploit code is available.

Is there a fix for CVE-2026-3395?

Fixed versions are available, including Maxsite CMS 109.2.

How urgently should CVE-2026-3395 be patched?

Brandefense priority: patch immediately, because it is listed as exploited in the wild.

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Vulnerability Intelligence

CVE-2026-3395

MediumExploitedPublic exploit

MaxSite CMS MarkItUp Preview AJAX Endpoint preview-ajax.php eval code injection

Published Mar 1, 2026 · Updated Aug 12, 2026

Key Facts

Patch immediately

CVE-2026-3395 is a medium-severity vulnerability (CVSS 5.5 v4) affecting Maxsite CMS (Max-3000).
It is exploited in the wild, listed in Industry KEV feed since Jul 9, 2026. Public exploit code is available.
EPSS estimates a 2.5% probability of exploitation in the next 30 days.
Fixed versions are available, including Maxsite CMS 109.2.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.

CVSS v4

5.5

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/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 (30-day exploit likelihood)

2.5%

Higher than 84.2% of all scored CVEs

Exploited in the wild

Yes

1 catalog listing

Public exploit code

Available

Proof-of-concept or weaponized module

Get the full CVE-2026-3395 brief as a PDF

Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.

Description

A flaw has been found in MaxSite CMS up to 109.1. This impacts the function eval of the file application/maxsite/admin/plugins/editor_markitup/preview-ajax.php of the component MarkItUp Preview AJAX Endpoint. Executing a manipulation can lead to code injection. It is possible to launch the attack remotely. The exploit has been published and may be used. Upgrading to version 109.2 will fix this issue. This patch is called 08937a3c5d672a242d68f53e9fccf8a748820ef3. You should upgrade the affected component. The code maintainer was informed beforehand about the issues. He reacted very fast and highly professional.

Known-Exploited Catalog Listings

Catalog	Added	Remediation due	Ransomware use
Industry KEV feed	Jul 9, 2026	n/a	Not reported

Required action: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Affected Products

2 affected entries in total

Product	Affected versions	Fixed in
Maxsite CMSMax-3000	>= 109.0	109.2

Patched Releases

Maxsite CMS

109.2

Timeline

Publicly disclosed
Mar 1, 2026
Added to Industry KEV feed
Jul 9, 2026
Last updated
Aug 12, 2026

Weakness Type

CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
CWE-94 Improper Control of Generation of Code ('Code Injection')

References

4 more references in the full CVE brief

FAQ

Common Questions.

A flaw has been found in MaxSite CMS up to 109.1.
Affected: Maxsite CMS (Max-3000) versions >= 109.0. The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Jul 9, 2026.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Maxsite CMS 109.2.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.

Is CVE-2026-3395 Running On Your Attack Surface?

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