CVE-2015-0842 in yubiserver
Summary
by MITRE • 06/27/2025
yubiserver before 0.6 is prone to SQL injection issues, potentially leading to an authentication bypass.
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Analysis
by VulDB Data Team • 06/30/2025
The vulnerability identified as CVE-2015-0842 affects yubiserver versions prior to 0.6, presenting a critical security flaw that stems from improper input validation within the authentication system. This SQL injection vulnerability exists in the server's handling of user credentials and authentication requests, creating a pathway for malicious actors to manipulate database queries through crafted input parameters. The flaw specifically impacts the server's ability to properly sanitize user-supplied data before incorporating it into SQL execution statements, which is a fundamental security weakness that violates basic secure coding practices.
The technical implementation of this vulnerability allows attackers to inject malicious SQL code through authentication requests, potentially enabling them to bypass the authentication mechanism entirely. When legitimate authentication requests are processed, the server fails to properly escape or parameterize user input, allowing attackers to manipulate the underlying database queries. This can result in unauthorized access to user accounts, data extraction, or even complete system compromise. The vulnerability is particularly dangerous because it operates at the authentication layer, meaning successful exploitation could provide attackers with access to all user credentials and potentially sensitive system information stored in the database.
From an operational perspective, this vulnerability creates significant risk for organizations relying on yubiserver for authentication services, as it directly undermines the core security function of the system. The impact extends beyond simple credential theft to potentially allow attackers to execute arbitrary database commands, modify user permissions, or gain elevated privileges within the system. The vulnerability aligns with CWE-89, which specifically addresses SQL injection flaws, and represents a classic example of how insecure data handling can compromise authentication systems. Organizations using affected versions face potential data breaches, unauthorized access to protected resources, and possible regulatory compliance violations depending on the nature of the data being protected.
Mitigation strategies for this vulnerability require immediate patching of yubiserver to version 0.6 or later, which includes proper input sanitization and parameterized query implementation. System administrators should also implement additional security measures such as database query monitoring, input validation at multiple layers, and regular security assessments of authentication systems. The remediation process should include thorough testing to ensure that the patch does not introduce compatibility issues with existing applications. Organizations should also review their database access controls and implement proper logging mechanisms to detect potential exploitation attempts. This vulnerability demonstrates the critical importance of maintaining up-to-date security software and implementing defense-in-depth strategies that protect authentication systems from common injection attacks. The ATT&CK framework categorizes this as a credential access technique, specifically involving the exploitation of authentication bypass vulnerabilities that can be leveraged to gain unauthorized system access.