Client Proxy (MCP) - Authentication Bypass vulnerability

published 2019-11-22 6y ago modified 2026-06-17 4mo ago also EUVD-2019-13289

cvss: 5.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 52%
public exploits: 0; none known

Authentication Bypass vulnerability in the Microsoft Windows client in McAfee Client Proxy (MCP) prior to 3.0.0 allows local user to bypass scanning of web traffic and gain access to blocked sites for a short period of time via generating an authorization key on the client which should only be generated by the network administrator.

Patch / fix

fixed in 1

McAfee Client Proxy (MCP) 3.0.0

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Exploit prediction

0.67% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.3	CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:N/I:N/A:H
NVD	3.1	8.6	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
NVD	2.0	6.8	AV:N/AC:M/Au:N/C:P/I:P/A:P

Affected products

McAfee Client Proxy (MCP)

Classification

Weakness

CWE-287 Improper Authentication

References

kc.mcafee.com /corporate/index?page=content&id=SB10305

Sources

CVE List CVE-2019-3654
NVD CVE-2019-3654

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