CVE-2026-25687: high-severity vulnerability in Zscaler Client Connector
ZCC race condition in ZPA tunnel handler
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.1epss 0.4%
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.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
Zscaler · Client ConnectorRelated CVEs — Zscaler Client Connector
In the same product, most dangerous first.
CVE-2024-23483HIGHLocal Privilege Escalation via lack of input validationEPSS 0.7%CVE-2026-59568CRITICALRemote Code ExecutionEPSS 0.7%CVE-2023-28800HIGHOutput encoding missing in redrurl parameterEPSS 0.5%CVE-2026-59564CRITICALAuthentication bypass between ZCC and client connector portalEPSS 0.5%CVE-2026-59565HIGHLocal and kernel denial-of-serviceEPSS 0.5%CVE-2024-23459HIGHMultiple Arbitrary Creates/Overwrites by link followingEPSS 0.5%