Name: CVE-2026-67399: Deserialization of Untrusted Data
Creator: Rapid7
Published: 2026-09-14T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-67399, CWE-502, CVSS 9.3, EPSS 0.00752

Deserialization of untrusted data in WHMCS 9.0.0 before 9.0.8 and 8.0.0 before 8.13.7 allows remote attackers to execute arbitrary code.

CVSS Details

CVSS 4.0 Base Score: 9.3 (CRITICAL)
CVSS 4.0 Vector: (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)

Prioritise with Active Threat Intelligence

With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.

Explore Intelligence Hub

MDR Buyer's Guide

Global Threat Landscape Report

Grow your business

CVSS Details

Prioritise with Active Threat Intelligence