How severe is CVE-2020-11635?

CVE-2020-11635 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-11635 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-11635?

CVE-2020-11635 affects Zscaler Client Connector. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-11635?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2020-11635 published?

CVE-2020-11635 was published on 2021-02-16 and last updated on 2026-06-17.

CVE-2020-11635

CVE-2020-11635 is a high-severity vulnerability in Zscaler Client Connector with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 7.2
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Zscaler Client Connector
Published: 2021-02-16
Last modified: 2026-06-17

Description

The Zscaler Client Connector prior to 3.1.0 did not sufficiently validate RPC clients, which allows a local adversary to execute code with system privileges or perform limited actions for which they did not have privileges.

Frequently asked questions

What is CVE-2020-11635?: The Zscaler Client Connector prior to 3.1.0 did not sufficiently validate RPC clients, which allows a local adversary to execute code with system privileges or perform limited actions for which they did not have privileges.
How severe is CVE-2020-11635?: CVE-2020-11635 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-11635 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-11635?: CVE-2020-11635 affects Zscaler Client Connector. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-11635?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-11635 published?: CVE-2020-11635 was published on 2021-02-16 and last updated on 2026-06-17.

References

https://trust.zscaler.com/posts/7316

Affected products (1)

cpe:2.3:a:zscaler:client_connector:*:*:*:*:*:windows:*:*

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