CVE-2020-4232 in Security Identity Governance
Summary
by MITRE
IBM Security Identity Governance and Intelligence 5.2.6 could allow an attacker to enumerate usernames to find valid login credentials which could be used to attempt further attacks against the system. IBM X-Force ID: 175336.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 10/19/2020
The vulnerability identified as CVE-2020-4232 affects IBM Security Identity Governance and Intelligence version 5.2.6, representing a critical weakness in the system's authentication mechanism that enables unauthorized username enumeration. This flaw exists within the identity governance platform that manages user access and authentication controls for enterprise environments. The vulnerability stems from insufficient input validation and error handling within the authentication service, allowing attackers to determine valid usernames through crafted requests that produce different responses than those for invalid accounts. This behavior creates a predictable pattern that adversaries can exploit to systematically identify legitimate user accounts within the system.
The technical implementation of this vulnerability involves the application's response differentiation when processing authentication requests for different user states. When an attacker submits a username that exists in the system, the server typically returns a different error message or response code compared to when an invalid username is submitted. This inconsistent behavior provides attackers with a reliable method to distinguish between valid and invalid usernames through repeated testing, effectively enabling account enumeration attacks. The vulnerability is particularly concerning because it operates at the authentication layer where user credentials are processed, making it a prime target for initial access exploitation. According to CWE classification, this represents a weakness in the system's input validation and error handling mechanisms, specifically categorized under CWE-20 Input Validation and Error Handling.
The operational impact of this vulnerability extends beyond simple credential theft, as it provides attackers with foundational intelligence for more sophisticated attacks within the target environment. Once valid usernames are identified, attackers can proceed with password spraying, brute force attacks, or social engineering campaigns targeting specific accounts. The vulnerability affects the overall security posture of organizations relying on IBM Security Identity Governance and Intelligence, as it undermines the principle of least privilege and creates opportunities for lateral movement within the network. Attackers can leverage this information to focus their efforts on accounts that are likely to have higher privileges or access to sensitive systems, making the initial enumeration phase particularly dangerous. This vulnerability aligns with several ATT&CK techniques including credential access methods such as credential dumping and valid accounts, as well as reconnaissance activities that precede more advanced exploitation phases.
Organizations should implement immediate mitigations to address this vulnerability, including enabling rate limiting on authentication requests to prevent automated enumeration attempts, implementing account lockout policies after failed login attempts, and configuring the system to return consistent error messages regardless of whether a username exists. Network-level protections such as intrusion detection systems and web application firewalls should be configured to monitor for patterns indicative of username enumeration attempts. Additionally, organizations should conduct comprehensive user account reviews to identify and strengthen credentials for accounts that may have been compromised through this vulnerability. The recommended remediation approach includes applying the official IBM security patches and updates, as well as implementing additional security controls such as multi-factor authentication to provide defense in depth against exploitation attempts. Regular security assessments and penetration testing should be conducted to verify that the implemented controls effectively prevent similar vulnerabilities from being exploited in other components of the identity governance infrastructure.