# CVE-2026-59565 — Zscaler Client Connector

> As of 2026-08-24, CVE-2026-59565 is a HIGH-severity vulnerability in Zscaler Client Connector, CVSS v3.1 8.8, EPSS 0.4% (39.2th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-59565, most recently “Multiple Zscaler Client Connector Flaws Enable Remote Code Execution (CVE-2026-59568)”.

**Last updated:** 2026-08-24

## What is CVE-2026-59565?

A remotely exploitable buffer overflow bug can cause a local and kernel denial-of-service attack on affected versions of Zscaler Client Connector on Windows.

The record classifies CVE-2026-59565 under weakness class [CWE-229](https://cwe.mitre.org/data/definitions/229.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs low-privilege credentials, needs no user interaction, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 65 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 8.8 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **EPSS (FIRST):** 0.4% probability of exploitation in the next 30 days, higher than 39.2% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 6/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-08-24

## Is CVE-2026-59565 being exploited?

It currently carries a trending score of 33 in the Threadlinqs vulnerability feed.

## Affected products and versions

- [Zscaler](https://intel.threadlinqs.com/vendors/zscaler): Client Connector

## How to fix CVE-2026-59565

No vendor patch reference has been recorded for CVE-2026-59565 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-59565

1 tracked threat in the Threadlinqs corpus references CVE-2026-59565, either in the campaign’s CVE list or as an indicator on the campaign record.

- [Multiple Zscaler Client Connector Flaws Enable Remote Code Execution (CVE-2026-59568)](https://intel.threadlinqs.com/threat/TL-2026-2139) — CRITICAL · 2026-08-25

## Sources

Enriched from CVE.org, FIRST EPSS. Last verified by Threadlinqs on 2026-10-10.

**Other references**

- [help.zscaler.com](https://help.zscaler.com/zscaler-client-connector/client-connector-app-release-summary-2026)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-59565
Full detection coverage and IOCs for threats exploiting CVE-2026-59565 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp