CVE-2015-5649 in Garoon
Summary
by MITRE
Cybozu Garoon 3.x through 3.7.5 and 4.x through 4.0.3 mishandles authentication requests, which allows remote authenticated users to conduct LDAP injection attacks, and consequently bypass intended login restrictions or obtain sensitive information, by leveraging certain group-administration privileges.
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Analysis
by VulDB Data Team • 01/26/2018
The vulnerability identified as CVE-2015-5649 affects Cybozu Garoon versions 3.x through 3.7.5 and 4.x through 4.0.3, representing a critical authentication flaw that undermines the security posture of these collaboration platforms. This issue stems from improper handling of authentication requests within the LDAP integration mechanisms, creating a pathway for malicious actors to exploit the system's trust model. The vulnerability specifically targets the group administration privileges that are typically restricted to authorized personnel, allowing attackers to manipulate authentication flows through carefully crafted LDAP queries.
The technical implementation of this vulnerability resides in the manner these Garoon versions process user authentication requests when LDAP directory services are configured. When legitimate users with group administration privileges attempt to authenticate, the system fails to properly sanitize or validate the input parameters that are passed to the underlying LDAP service. This insufficient input validation creates an injection vector where attackers can manipulate the LDAP query syntax to bypass normal authentication restrictions. The flaw operates at the intersection of authentication and directory service integration, where the system's trust in the LDAP backend is exploited through malformed input that alters the intended query execution path.
From an operational perspective, this vulnerability enables remote authenticated users to conduct LDAP injection attacks that can result in significant security implications including privilege escalation, unauthorized access to sensitive information, and potential lateral movement within the network. The attack requires the adversary to possess valid credentials for the Garoon system, but the vulnerability allows them to leverage their authenticated session to bypass intended access controls that should restrict their privileges based on group membership and administrative roles. The impact extends beyond simple authentication bypass as it can expose sensitive organizational data that would normally be protected by proper access controls.
The vulnerability aligns with CWE-91 and CWE-90 categories, specifically addressing weaknesses in LDAP injection and improper neutralization of special elements used in an LDAP query. It also maps to several ATT&CK techniques including T1078 for valid accounts and T1071.004 for application layer protocol usage. Organizations utilizing these affected Garoon versions face potential exposure to credential compromise and unauthorized data access, particularly in environments where LDAP integration is used for user authentication and authorization. The attack vector is particularly concerning as it operates within the legitimate authentication flow, making detection more challenging and potentially allowing attackers to remain undetected while exploiting the privilege escalation capabilities.
Mitigation strategies should focus on immediate patch deployment for the affected versions, implementing proper input validation and sanitization for all LDAP query parameters, and restricting group administration privileges to only essential personnel. Network segmentation and monitoring of LDAP traffic can help detect anomalous authentication patterns that may indicate exploitation attempts. Additionally, organizations should review their LDAP integration configurations to ensure proper parameter binding and avoid direct concatenation of user input into LDAP queries. The remediation process should include comprehensive testing to ensure that the patch does not disrupt legitimate authentication flows while effectively addressing the injection vulnerability.