CVE-2026-59565: zscaler client_connector Improper Handling of Values
CVSS: 8.8v3.1HighAwaiting analysis
Published 24-08-2026Last modified 24-08-2026
Vulnerability summary
CVE-2026-59565 is a high (CVSS 8.8) Improper Handling of Values vulnerability in zscaler client_connector. EPSS estimates a 0.48% chance of exploitation in the next 30 days, higher than 40.1% of scored vulnerabilities.
CVSS score
8.8/10
010
High · v3.1 (CVE.org)EPSS score
0.48%
0%100%
Low · +0.21 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 24-08-2026PublishedVulnerability first disclosed.
- 24-08-2026Last modifiedVulnerability information updated.
Description
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.
CVSS metrics
2 scores · 2 sources · 1 versionHigh 8.8Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HSourcesAll 2 agree
- NVDNIST8.8HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.48%
Chance of exploitation in the next 30 days
Percentile
40%
Versus all other CVEs
30-day change
+0.21 pp
From 0.27% on 21-09-2026
21-09-202621-10-2026
EPSS score0.48%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Zscaler1 product
- client_connector< Windows: 4.6.0.457, 4.7.0.317, 4.8.0.232, 4.9.0.372
1 vendor · 1 product