CVE-2026-20211
CriticalCVSS 9.1Summary
Vulnerability in Cisco ISE allows an authenticated remote attacker with high-privileged admin credentials to execute arbitrary commands on the underlying OS. It is due to insecure deserialization of Java objects. Single-node deployments may experience DoS.
Risk Assessment
An attacker with admin privileges can gain full system control, and in single-node deployments may cause network unavailability for unauthenticated endpoints.
Recommendation
Restrict administrative access and apply patches from Cisco. Monitor logs for suspicious activity.
Other vulnerabilities in Cisco Identity Services Engine
See all- CVE-2026-76460CriticalActively exploited
A vulnerability in the API of Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to bypass authentication. This is due to insufficient authentication control on an API endpoint. An attacker could send a crafted request to gain unauthorized access to the device by bypassing the web-based management interface.
- CVE-2026-20284Critical
A vulnerability in the SXP REST API of Cisco ISE could allow an authenticated, remote attacker to conduct SQL injection attacks. This is due to insufficient validation of user-supplied input in REST API calls. A successful exploit could allow the attacker to view or modify data on the underlying database, and in single-node deployments could cause a DoS condition.
- CVE-2026-20237Critical
Vulnerability in Cisco Identity Services Engine (ISE) and ISE Passive Identity Connector (ISE-PIC) is due to improper input validation issues (CWE-20). It was discovered during an internal security review and addressed in a hardening release.
- CVE-2026-20194Critical
Vulnerability in Cisco Identity Services Engine (ISE) and ISE Passive Identity Connector (ISE-PIC) is due to incorrect resource transfer between spheres (CWE-669). It was discovered during an internal security review and addressed in a hardening release.
- CVE-2026-20192Critical
Vulnerability in Cisco Identity Services Engine (ISE) and ISE Passive Identity Connector (ISE-PIC) is due to improper access control issues (CWE-284). It was discovered during an internal security review and addressed in a hardening release.
- CVE-2026-20176Critical
Vulnerability in Cisco ISE allows an authenticated remote attacker with high-privileged admin credentials to execute arbitrary commands on the underlying OS. It is due to insufficient validation of user-supplied input. Single-node deployments may experience DoS.
- CVE-2026-20130Critical
Vulnerability in Cisco Identity Services Engine (ISE) and ISE Passive Identity Connector (ISE-PIC) is due to improper neutralization of special elements (CWE-74). It was discovered during an internal security review and addressed in a hardening release.
- CVE-2026-20186Critical
A vulnerability in Cisco Identity Services Engine (ISE) allows an authenticated remote attacker to execute arbitrary commands on the underlying OS. The attacker needs at least Read Only Admin credentials and sends a crafted HTTP request.
- CVE-2026-20180Critical
A vulnerability in Cisco Identity Services Engine (ISE) allows an authenticated remote attacker to execute arbitrary commands on the underlying OS. The attacker needs at least Read Only Admin credentials and sends a crafted HTTP request.
- CVE-2026-20146Medium
A vulnerability in Cisco Identity Services Engine (ISE) and Cisco ISE Passive Identity Connector (ISE-PIC) allows an authenticated remote attacker to perform path traversal attacks on the underlying operating system. The attacker can read or delete arbitrary files by sending a crafted HTTP request.
Original NVD description (English source)
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 could allow the attacker to obtain user-level access to the underlying operating system and then 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 DoS condition. In that condition, endpoints that have not already authenticated would be unable to access the network until the node is restored.

