MaxSite CMS up to 109.1 MarkItUp Preview AJAX Endpoint preview-ajax.php eval code injection

CVSS Meta Temp Score
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CTI Interest Score
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8.4$0-$5k0.45

Summaryinfo

A vulnerability has been found in MaxSite CMS up to 109.1 and classified as critical. Affected is the function eval of the file application/maxsite/admin/plugins/editor_markitup/preview-ajax.php of the component MarkItUp Preview AJAX Endpoint. The manipulation leads to code injection. This vulnerability is documented as CVE-2026-3395. The attack can be initiated remotely. Additionally, an exploit exists. The affected component should be upgraded. The code maintainer was informed beforehand about the issues. He reacted very fast and highly professional.

Detailsinfo

A vulnerability was found in MaxSite CMS up to 109.1. It has been rated as critical. This issue affects the function eval of the file application/maxsite/admin/plugins/editor_markitup/preview-ajax.php of the component MarkItUp Preview AJAX Endpoint. The manipulation with an unknown input leads to a code injection vulnerability. Using CWE to declare the problem leads to CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. Impacted is confidentiality, integrity, and availability.

The identification of this vulnerability is CVE-2026-3395. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details as well as a public exploit are known. MITRE ATT&CK project uses the attack technique T1059 for this issue.

It is declared as proof-of-concept. The code maintainer was informed beforehand about the issues. He reacted very fast and highly professional. By approaching the search of inurl:application/maxsite/admin/plugins/editor_markitup/preview-ajax.php it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 109.2 eliminates this vulnerability. Applying the patch 08937a3c5d672a242d68f53e9fccf8a748820ef3 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-9130). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 6.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

Researcher Base Score: 9.8
Researcher Vector: 🔒

NVD Base Score: 9.8
NVD Vector: 🔒

CNA Base Score: 7.3
CNA Vector: 🔒

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Researcher Base Score: 🔒

Exploitinginfo

Class: Code injection
CWE: CWE-94 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Google Hack: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: CMS 109.2
Patch: 08937a3c5d672a242d68f53e9fccf8a748820ef3

Timelineinfo

02/28/2026 Advisory disclosed
02/28/2026 +0 days VulDB entry created
03/05/2026 +5 days VulDB entry last update

Sourcesinfo

Product: github.com

Status: Confirmed

CVE: CVE-2026-3395 (🔒)
GCVE (CVE): GCVE-0-2026-3395
GCVE (VulDB): GCVE-100-348281
EUVD: 🔒
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 02/28/2026 18:20
Updated: 03/05/2026 03:02
Changes: 02/28/2026 18:20 (60), 03/01/2026 02:32 (6), 03/01/2026 02:33 (8), 03/01/2026 02:36 (4), 03/01/2026 20:03 (31), 03/01/2026 21:10 (1), 03/03/2026 15:23 (1), 03/05/2026 03:02 (10)
Complete: 🔍
Submitter: mrsolo404
Committer: mrsolo404
Cache ID: 216::103

Submitinfo

Accepted

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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