CVE-2025-54983: Health check port on ZCC allows tunnel bypass

Description

A health check port on Zscaler Client Connector on Windows, versions 4.6 < 4.6.0.216 and 4.7 < 4.7.0.47, which under specific circumstances was not released after use, allowed traffic to potentially bypass ZCC forwarding controls.

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Attack vector

Local

Complexity

Low

Privileges

Low

User interaction

None

Confidentiality

Low

Integrity

Low

Availability

None

Scope

Changed

Exploitation

Is it being used?

Exploit prediction (EPSS)0.1% · higher than 3% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

ZC

Zscaler Client Connector · Zscaler

4.6 before 4.6.0.216; 4.7 before 4.7.0.47 · source: vendor