Vulnerability · Published Sep 14, 2026 · Assigned by Zscaler
CVE-2026-25687ZCC race condition in ZPA tunnel handler
High 8.1
In plain English
A high-severity security flaw in Client Connector from Zscaler. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 32% of all known vulnerabilities).
Severity (CVSS 3.1)8.1High
Exploit odds (30 days)0.4%top 67.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Zscaler | Client Connector | 4.6 – before 4.6.0.4864.7 – before 4.7.0.3504.8 – before 4.8.0.2674.9 – before 4.9.0.412 |
Weakness: CWE-366 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H