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CVE-2026-19377

Improper certificate validation in Cato Client tunnel handshake

CVSS score

6.0

EPSS probability

%0.1

Risk score

0.0

Published

9 h ago

OverviewPublic Exploits (0)NewsroomVulnerability Timeline
Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

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Vulnerability description

CVE AI research

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DayBreach AI Explanation

Verified against sources

Improper Certificate Validation Vulnerability in Cato Client Tunnel Handshake via CVE-2026-19377

Sources read

2

Source agreement

Tam uyum

Evidence confidence

%63

Short explanation

CVE-2026-19377 is a vulnerability involving improper certificate validation during the Cato Client tunnel handshake [S0]. It allows a man-in-the-middle attacker to impersonate a Cato Point of Presence server [S0].

Why does it matter?

This vulnerability poses confidentiality and integrity risks by enabling attackers to intercept or modify tunnel traffic [S0].

What should be done?

  • Follow the vendor advisory
Chain of evidence and sources2 verified claims

Cato Client tünel el sıkışmasındaki uygunsuz sertifika doğrulaması, bir saldırganın Cato Point of Presence sunucusunu taklit etmesine izin verir.

S0 · daybreach-canonicalS1 · cvelist

Zafiyet, tünel trafiğinin aradaki bir saldırgan tarafından ele geçirilmesine veya değiştirilmesine olanak tanır.

S0 · daybreach-canonicalS1 · cvelistS2 · nvd
Show the technical text from the sources

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.

CVSS 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

CWE: CWE-295

Explanation produced with the local gemini-flash-lite-latest model. Numerical metrics and the KEV, patch and exploit statuses are not determined by AI.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-19377 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1Cato NetworksCato Client for Windows View
2Cato NetworksCato Client for macOS View
3Cato NetworksCato Client for Linux View
4Cato NetworksCato Client for iOS View
5Cato NetworksCato Client for Android View
Total affected vendors: 1|Products: 5

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
6.0CVSS V40MEDIUMCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/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:XNVD
6.0CVSS V4_0MEDIUMCVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:NCVE CNA

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-19377 is associated with the following CWEs:

CWE-295: Common Weakness Enumeration Entry CWE-295

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-19377 weaknesses.

CAPEC-66: SQL InjectionCAPEC-126: Path TraversalCAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureBitişik ağ
PermissionsGerekmiyor
UserGerekmiyor

Official Sources and Advisories

Cato Networks Security Advisoryvendor-advisory

CVSS Vector Radar Chart

6.0 / 10
Attack VectorAdjacentComplexityLowPrivilegesNoneUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityNone

Vulnerability Scoring Details

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
Attack VectorAdjacent network
Attack ComplexityLow
Privileges RequiredNone required
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)None

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Follow the vendor

CN
Cato Networks logo
Cato Networks

Weakness Type (CWE & CAPEC)

CWE-295

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CVE-2026-19377 · Improper certificate validation in Cato Client tunnel handshake · DayBreach