CVE-2026-70553

MaxSite CMS contains a remote code execution vulnerability that allows unauthenticated attackers to inject arbitrary PHP code into the application configuration file by submitting crafted POST requests to the install endpoint after installation is complete. Attackers can supply a malicious db_dbprefix value containing a single quote to break out of a PHP string literal in application/config/database.php, appending attacker-controlled PHP statements that are executed by the web server on every subsequent request, resulting in persistent unauthenticated remote code execution as the web-server process user.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/maxsite/cms
https://max-3000.com/page/maxsite-cms-109-6
https://www.vulncheck.com/advisories/maxsite-cms-unauthenticated-rce-via-install-endpoint

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-04 20:16

Updated : 2026-08-31 20:19

NVD link : CVE-2026-70553

Mitre link : CVE-2026-70553

CVE.ORG link : CVE-2026-70553

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

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