CVE-2026-67399NVD

Vulnerability Summary

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.

Severity Level

UNKNOWN

Published Date

Sep 14, 2026

Last Modified

Sep 15, 2026

Exploitation Status

No confirmed exploitation yet

EPSS Score (30-Day)

0.75%Probability

Root Weakness (CWE)

CWE-502: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v4.0 Base Metrics — Score 9.3 (CRITICAL)

Attack VectorNetwork

Attack ComplexityLow

Attack RequirementsNone

Privileges RequiredNone

User InteractionNone

Confidentiality (Vulnerable System)High

Integrity (Vulnerable System)High

Availability (Vulnerable System)High

Confidentiality (Subsequent System)None

Integrity (Subsequent System)None

Availability (Subsequent System)None

Affected & Patched Versions

Affected Versions

WebPros WHMCS >= 9.0.0 and < 9.0.8
WebPros WHMCS >= 8.0.0 and < 8.13.7

Patched Versions

WebPros WHMCS 9.0.8
WebPros WHMCS 8.13.7

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