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CRITICAL

CVE-2026-20211

CVSS v3

9.1

CRITICAL

EPSS Score

0.6 %

exploit probability, as of 2026-09-29

CISA KEV

No

known exploited

Exploitation

—

SSVC status

Description

A vulnerability in Cisco ISE could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. To exploit this vulnerability, the attacker must have valid high-privileged administrative credentials. This vulnerability is due to insecure deserialization of Java objects by the affected software. An attacker could exploit this vulnerability by sending a crafted serialized Java object to an affected device. A successful exploit c

Technical details

Published
2026-09-16
Last Modified
2026-09-17

Frequently asked questions

What is CVE-2026-20211?

A vulnerability in Cisco ISE could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. To exploit this vulnerability, the attacker must have valid high-privileged administrative credentials. This vulnerability is due to insecure deserialization of Java objects by the affected software. An attacker could exploit this vulnerability by sending a crafted serialized Java object to an affected device. A successful exploit c

Is CVE-2026-20211 actively exploited?

Active exploitation of CVE-2026-20211 has not been confirmed. Its EPSS score was 0.6% on 2026-09-29, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-20211?

CVE-2026-20211 has a CVSS v3 base score of 9.1 (CRITICAL severity).

Is CVE-2026-20211 affecting your environment?

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