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ZscalerCVE-2026-25687

Zscaler Client Connector: race condition

High8.1CVE-2026-25687 · Published Sep 14, 2026 · updated Sep 18, 2026

A race condition in the ZPA tunnel handler of affected versions of Zscaler Client Connector (ZCC) allows a heap corruption, resulting in a denial of service (client crash) and potentially arbitrary code execution in the context of the ZCC process.

Zscaler advisory

Affected versions

PackageAffectedFixed in
Client Connector
Product
>= 4.6, < 4.6.0.4864.6.0.486
>= 4.7, < 4.7.0.3504.7.0.350
>= 4.8, < 4.8.0.2674.8.0.267
>= 4.9, < 4.9.0.4124.9.0.412
Details and references
CVSS 3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Severity from
the vendor (its own CVE record or advisory)
Weakness
CWE-366

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