CVE-2015-4331 in Prime Infrastructure
Summary
by MITRE
Cisco Prime Infrastructure (PI) 1.4(0.45) and earlier, when AAA authentication is used, allows remote authenticated users to bypass intended access restrictions via a username with a modified composition of lowercase and uppercase characters, aka Bug ID CSum59958.
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Analysis
by VulDB Data Team • 06/13/2022
Cisco Prime Infrastructure version 1.4(0.45) and earlier contains a critical authentication bypass vulnerability that affects systems utilizing AAA (Authentication, Authorization, and Accounting) services. This vulnerability stems from improper handling of username case sensitivity during the authentication process, creating a pathway for malicious actors to exploit the system's access controls. The flaw specifically manifests when users with valid credentials attempt to authenticate using usernames that have been modified through strategic manipulation of uppercase and lowercase character arrangements. This issue represents a significant weakness in the system's identity verification mechanisms and directly undermines the security posture of organizations relying on Cisco Prime Infrastructure for network management.
The technical implementation of this vulnerability exploits the system's failure to properly normalize or validate username case variations during authentication processing. When a user submits a username with modified character casing, the system does not adequately enforce consistent case handling, allowing certain modified username compositions to bypass the intended access controls that should restrict user permissions based on their authenticated identity. This behavior creates a scenario where authenticated users can potentially access resources or perform actions that should be restricted to specific user roles or privileges. The vulnerability operates at the authentication layer and leverages the system's insufficient input validation and case handling routines, which are fundamental security controls that should prevent such bypass scenarios. This type of flaw aligns with CWE-287, which addresses improper handling of authentication tokens and credentials, and represents a direct violation of proper authentication protocol implementation.
The operational impact of CVE-2015-4331 extends beyond simple unauthorized access, potentially enabling attackers to escalate privileges within the network management environment. Organizations utilizing Cisco Prime Infrastructure may face scenarios where unauthorized users gain access to sensitive network configuration data, management interfaces, or operational controls that should be restricted to authorized administrators only. The vulnerability affects the integrity of the AAA authentication system, which is fundamental to maintaining secure network operations and preventing unauthorized access to critical infrastructure components. Attackers could exploit this weakness to perform actions such as viewing network device configurations, modifying network settings, or accessing sensitive operational data. The consequences could include unauthorized network modifications, data exfiltration, or disruption of network services, all of which could severely impact business continuity and security operations. This vulnerability particularly affects organizations that depend on centralized network management systems for their infrastructure security posture.
Mitigation strategies for CVE-2015-4331 should prioritize immediate implementation of the vendor-provided security patches and updates for Cisco Prime Infrastructure. Organizations must ensure that all affected systems are updated to versions that properly address the username case handling behavior within the AAA authentication framework. Network administrators should also implement additional monitoring and logging controls to detect unusual authentication patterns or attempts to exploit the vulnerability. The implementation of proper input validation procedures and consistent case normalization should be enforced across all authentication systems to prevent similar vulnerabilities from emerging. Organizations should conduct comprehensive security assessments of their network management infrastructure to identify any additional systems that may be vulnerable to similar case sensitivity issues. Configuration reviews should include verification that authentication systems properly handle all character variations and that access controls are enforced consistently regardless of username composition. This vulnerability serves as a reminder of the importance of proper credential validation and authentication protocol implementation, aligning with ATT&CK technique T1078 for valid accounts and T1566 for credential harvesting, which emphasizes the need for robust authentication mechanisms to prevent unauthorized access through compromised credentials.