CVE-2022-20965: Cisco ISE Auth Bypass Vulnerability

CVE-2022-20965 Overview

A vulnerability in the web-based management interface of Cisco Identity Services Engine (ISE) could allow an authenticated, remote attacker to take privileged actions within the web-based management interface. This vulnerability is due to improper access control on a feature within the web-based management interface of the affected system.

An attacker could exploit this vulnerability by accessing features through direct requests, bypassing checks within the application. A successful exploit could allow the attacker to take privileged actions within the web-based management interface that should be otherwise restricted.

Critical Impact

Authenticated attackers can bypass access controls and perform privileged administrative actions on Cisco ISE deployments, potentially compromising network access control policies and authentication infrastructure.

Affected Products

• Cisco Identity Services Engine 2.6.0 (including patches 1-12)
• Cisco Identity Services Engine 2.7.0 (including patches 1-7)
• Cisco Identity Services Engine 3.0.0 (including patches 1-6)
• Cisco Identity Services Engine 3.1 (including patches 1, 3, 4)
• Cisco Identity Services Engine 3.2

Discovery Timeline

• January 20, 2023 - CVE-2022-20965 published to NVD
• November 21, 2024 - Last updated in NVD database

Technical Details for CVE-2022-20965

Vulnerability Analysis

This vulnerability represents a Broken Access Control (CWE-648: Incorrect Use of Privileged APIs) issue within the Cisco Identity Services Engine web-based management interface. The application fails to properly enforce authorization checks when processing direct HTTP requests to privileged functionality.

The flaw allows authenticated users with limited privileges to access administrative features by crafting direct requests to the application endpoints. This bypasses the normal access control mechanisms that would restrict these actions through the standard user interface navigation.

Cisco ISE is a critical network access control solution that manages authentication, authorization, and accounting (AAA) for enterprise networks. Compromise of this system could allow attackers to modify network access policies, manipulate authentication rules, or gain access to sensitive network configuration data.

Root Cause

The root cause of this vulnerability is improper access control implementation on specific features within the web-based management interface. The application relies on client-side controls or inadequate server-side validation to restrict access to privileged functionality. When users make direct HTTP requests to these features, the backend fails to verify whether the authenticated user has the appropriate privilege level to perform the requested action.

This architectural weakness allows low-privileged authenticated users to escalate their access by directly invoking API endpoints or management functions that should only be available to administrators.

Attack Vector

The attack vector is network-based, requiring the attacker to have authenticated access to the Cisco ISE web-based management interface. The exploitation process involves:

1. An attacker first authenticates to the Cisco ISE web interface with any valid user credentials
2. The attacker identifies privileged features or API endpoints through reconnaissance
3. The attacker crafts direct HTTP requests to these endpoints, bypassing the normal UI-based access controls
4. The server processes these requests without proper authorization validation, executing the privileged actions

This vulnerability does not require user interaction and can be exploited with low attack complexity once authenticated access is obtained.

Detection Methods for CVE-2022-20965

Indicators of Compromise

• Unusual administrative actions performed by low-privileged user accounts in ISE audit logs
• Direct API requests to privileged endpoints from non-administrator sessions
• Unexpected changes to network access policies, authentication configurations, or user permissions
• HTTP requests to administrative URLs from user sessions that should not have access to those features

Detection Strategies

• Review Cisco ISE audit logs for privilege escalation attempts and unauthorized administrative actions
• Monitor for direct HTTP requests to administrative endpoints that bypass normal navigation patterns
• Implement web application firewall (WAF) rules to detect and alert on direct access attempts to privileged functionality
• Deploy SentinelOne Singularity to monitor endpoint and network activity for signs of exploitation attempts

Monitoring Recommendations

• Enable verbose logging on Cisco ISE to capture all administrative actions and user session activities
• Configure SIEM correlation rules to detect low-privileged users performing administrative operations
• Regularly audit user permissions and access patterns within the ISE management interface
• Monitor network traffic to ISE management interfaces for anomalous request patterns

How to Mitigate CVE-2022-20965

Immediate Actions Required

• Apply the latest security patches from Cisco as described in the official security advisory
• Restrict access to the ISE web-based management interface to trusted networks only
• Implement network segmentation to limit who can reach the ISE management plane
• Review and audit all user accounts with access to ISE, removing unnecessary privileges

Patch Information

Cisco has released security updates to address this vulnerability. Organizations should refer to the Cisco Security Advisory cisco-sa-ise-7Q4TNYUx for specific patch versions and upgrade instructions applicable to their ISE deployment.

Administrators should upgrade to a fixed software release as soon as possible to fully remediate this vulnerability.

Workarounds

• Limit network access to the ISE management interface using ACLs or firewall rules
• Implement role-based access control (RBAC) and regularly audit user permissions
• Use a bastion host or jump server for administrative access to ISE
• Enable multi-factor authentication (MFA) for all ISE administrative accounts

# Example: Restrict ISE management access using network ACLs
# Apply ACL to limit management interface access to trusted admin networks
ip access-list extended ISE-MGMT-RESTRICT
 permit tcp 10.1.100.0 0.0.0.255 host 10.1.1.10 eq 443
 permit tcp 10.1.100.0 0.0.0.255 host 10.1.1.10 eq 80
 deny ip any host 10.1.1.10