CVE-2026-19377 json
Improper certificate validation in Cato Client tunnel handshake
published 2026-10-15 25 d ago modified 2026-10-16 23 d ago also EUVD-2026-101881
- cvss
- 6.0
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.1%
- EPSS 0.1% chance of exploitation in 30 days, percentile 0%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- Cato Networks Cato Client for Windows 6.12.6
- Cato Networks Cato Client for macOS 6.1.1
- Cato Networks Cato Client for Linux 5.8.1
- Cato Networks Cato Client for iOS 5.9
- Cato Networks Cato Client for Android 5.6.2
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 25 d ago
Exploit prediction
0.08% chance of exploitation in the next 30 days, higher than 0% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.0 | 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 |
| CNA | 4.0 | 6.0 | 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/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 |
Affected products
- Cato Networks Cato Client for Windows
- Cato Networks Cato Client for macOS
- Cato Networks Cato Client for Linux
- Cato Networks Cato Client for iOS
- Cato Networks Cato Client for Android
Classification
- Weakness
-
- CWE-295 Improper Certificate Validation
References
Sources
- CVE List CVE-2026-19377
- NVD CVE-2026-19377
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