๐Ÿ” CVE Alert

CVE-2026-20307

CRITICAL 9.9

Cisco Identity Services Engine Remote Code Execution Vulnerability

CVSS Score
9.9
EPSS Score
0.0%
EPSS Percentile
0th

A vulnerability in the web-based management interface of 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 at least low-privileged administrative credentials. This vulnerability is due to insecure deserialization of a user-supplied Java byte stream. An attacker could exploit this vulnerability by sending a crafted serialized Java object to the web-based management interface of an affected device. A successful exploit could allow the attacker to execute arbitrary code on the device and elevate privileges to root. In single-node deployments, successful exploitation of this vulnerability could cause the affected ISE node to become unavailable, resulting in a denial of service (DoS) condition. In that condition, endpoints that have not already authenticated would be unable to access the network until the node is restored.

CWE CWE-502
Vendor cisco
Product cisco identity services engine software
Ecosystems
Industries
NetworkingTelecommunications
Published Sep 16, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

Affected Versions

Cisco / Cisco Identity Services Engine Software
3.1.0 3.1.0 p1 3.1.0 p3 3.1.0 p2 3.2.0 3.1.0 p4 3.1.0 p5 3.2.0 p1 3.1.0 p6 3.2.0 p2 3.1.0 p7 3.3.0 3.2.0 p3 3.2.0 p4 3.1.0 p8 3.2.0 p5 3.2.0 p6 3.1.0 p9 3.3 Patch 2 3.3 Patch 1 3.3 Patch 3 3.4.0 3.2.0 p7 3.3 Patch 4 3.4 Patch 1 3.1.0 p10 3.3 Patch 5 3.3 Patch 6 3.4 Patch 2 3.3 Patch 7 3.4 Patch 3 3.5.0 3.4 Patch 4 3.3 Patch 8 3.2 Patch 8 3.5 Patch 1 3.3 Patch 9 3.2 Patch 9 3.4 Patch 5 3.5 Patch 3 3.5 Patch 2 3.3 Patch 10 3.3 Patch 11 3.4 Patch 6 3.2 Patch 10 3.1.0 p72 3.1.0 p11

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
sec.cloudapps.cisco.com: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-rce-se7bYU57