CVE-2021-36201 in C-CURE 9000
Summary
by MITRE • 10/12/2022
Under certain circumstances a CCURE Portal user could enumerate user accounts in CCURE 9000 version 2.90 and prior versions.
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Analysis
by VulDB Data Team • 11/05/2022
The vulnerability identified as CVE-2021-36201 represents a critical information disclosure flaw within the CCURE 9000 security platform, specifically affecting versions 2.90 and earlier. This issue manifests as an account enumeration vulnerability that allows unauthorized users to discover valid user accounts within the system. The vulnerability stems from insufficient input validation and inadequate error handling mechanisms within the authentication and user management components of the CCURE Portal. Attackers can exploit this weakness by sending crafted requests to the system's authentication endpoints, which then provide distinguishable responses for valid versus invalid usernames, thereby enabling systematic enumeration of all active accounts.
The technical exploitation of this vulnerability follows a pattern where attackers send authentication requests with various username inputs and analyze the system's response behavior to determine which accounts exist within the directory. This type of vulnerability is classified under CWE-200, which encompasses information exposure issues, and represents a significant deviation from secure authentication practices that should maintain consistent response times and error messages regardless of whether a user account exists. The flaw essentially violates fundamental security principles by providing attackers with information that should remain confidential, directly enabling credential stuffing attacks, brute force attempts, and social engineering operations against the enumerated accounts.
From an operational impact perspective, this vulnerability creates substantial risk for organizations utilizing CCURE 9000 systems, as it provides attackers with a comprehensive list of valid usernames that can be used in conjunction with other attack vectors. The enumeration capability significantly reduces the complexity of subsequent attacks, as attackers no longer need to guess valid usernames through random attempts. This vulnerability directly maps to ATT&CK technique T1078 which covers valid accounts and credential access, as it provides the initial foothold necessary for unauthorized access. Organizations may experience cascading security issues where the enumeration leads to successful compromise of multiple user accounts, particularly if weak passwords or shared credentials exist within the enumerated user base.
The mitigation strategies for CVE-2021-36201 require immediate attention through software updates and configuration hardening measures. Organizations should prioritize upgrading to CCURE 9000 version 2.91 or later, which contains the necessary patches to address the account enumeration vulnerability. Additionally, implementing consistent error handling across all authentication endpoints ensures that the system provides identical response patterns regardless of whether a username exists in the directory. Network-level protections such as rate limiting, IP address monitoring, and intrusion detection systems can help detect and prevent automated enumeration attempts. Security teams should also implement account lockout mechanisms and monitor authentication logs for suspicious patterns that indicate enumeration activities, aligning with security best practices outlined in NIST SP 800-53 and ISO 27001 standards for access control and authentication management.