CVE-2026-70553

critical · 9.3

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.

9.3

CVSS

1.2%

EPSS (exploit prob.)

67th

EPSS percentile

2026-08-04

Published

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/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

Weaknesses

CWE-94

References

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

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-70553