CVE-2026-19377 - Vulnerability Details - OpenCVE

Improper certificate validation in the tunnel handshake in Cato Client allows a man-in-the-middle attacker to impersonate a Cato Point of Presence (PoP) server and intercept or modify tunnel traffic.

Attack Vector Adjacent Network

Attack Complexity Low

Privileges Required None

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact Low

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00083.

Exploitation none

Automatable no

Technical Impact partial

No data.

No data.

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Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

Link	Providers
https://knowledge.catonetworks.com/docs/security-vulnerability-cve-2026-19377-that-impacts-cato-client-versions

History

Thu, 15 Oct 2026 15:30:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Thu, 15 Oct 2026 13:30:00 +0000

Type	Values Removed	Values Added
Description		Improper certificate validation in the tunnel handshake in Cato Client allows a man-in-the-middle attacker to impersonate a Cato Point of Presence (PoP) server and intercept or modify tunnel traffic.
Title		Improper certificate validation in Cato Client tunnel handshake
Weaknesses		CWE-295
References		https://knowledge.catonetworks.com/docs/security-vulnerability-cve-2026-19377-that-impacts-cato-client-versions
Metrics		cvssV4_0 `{'score': 6, 'vector': 'CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: Cato

Published: 2026-10-15T07:02:10.937Z

Updated: 2026-10-15T14:22:58.368Z

Reserved: 2026-08-09T13:31:39.053Z

Link: CVE-2026-19377

Vulnrichment

Updated: 2026-10-15T14:22:54.882Z

NVD

Status : Received

Published: 2026-10-15T07:17:59.143

Modified: 2026-10-15T15:17:31.433

Link: CVE-2026-19377

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-295

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