CVE-2016-0726 in Nagios
Summary
by MITRE
The Fedora Nagios package uses "nagiosadmin" as the default password for the "nagiosadmin" administrator account, which makes it easier for remote attackers to obtain access by leveraging knowledge of the credentials.
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Analysis
by VulDB Data Team • 12/26/2020
The vulnerability described in CVE-2016-0726 represents a critical security misconfiguration within the Fedora Nagios package that exposes administrative access to remote attackers through predictable default credentials. This issue affects network monitoring systems that rely on Nagios for infrastructure oversight, creating a significant attack surface that adversaries can exploit without requiring advanced techniques or specialized tools. The flaw stems from the package's default configuration where the administrative account nagiosadmin is assigned the password nagiosadmin, a practice that violates fundamental security principles of credential management and access control. This vulnerability directly aligns with CWE-798, which categorizes the use of hard-coded credentials as a serious weakness that enables unauthorized access to systems. The default credential approach creates a persistent risk that remains active until explicitly addressed by system administrators, making it particularly dangerous in environments where monitoring systems are critical infrastructure components.
The technical exploitation of this vulnerability occurs when remote attackers can identify the default administrative credentials through various reconnaissance methods including automated scanning tools, public databases of default credentials, or simple social engineering approaches. Once authenticated, attackers gain full administrative privileges within the Nagios monitoring environment, which provides them with complete visibility into monitored systems and the ability to manipulate monitoring data, disable alerts, or even compromise the underlying infrastructure. The impact extends beyond simple unauthorized access as Nagios systems often serve as central points for network monitoring and security event correlation, making them attractive targets for attackers seeking to maintain persistent access or conduct reconnaissance. This vulnerability also relates to ATT&CK technique T1078 which covers valid accounts as a means of gaining access to systems, specifically highlighting how default credentials can be leveraged to establish unauthorized access. The configuration error allows for immediate privilege escalation without requiring additional exploitation techniques, making it particularly dangerous for organizations that fail to properly secure their monitoring infrastructure.
The operational impact of CVE-2016-0726 creates a substantial risk for organizations relying on Nagios monitoring systems, as it provides attackers with unrestricted access to critical infrastructure monitoring capabilities. Security teams lose visibility into their network operations and may be unaware of ongoing compromise, as attackers can manipulate or disable monitoring alerts to avoid detection. The vulnerability affects the integrity and availability of monitoring data, potentially allowing attackers to cover their tracks or manipulate security events to prevent detection. Organizations may face regulatory compliance issues if monitoring systems are compromised, as audit trails and security event logging become unreliable. The risk is compounded by the fact that many organizations deploy Nagios systems across multiple environments without proper credential management, creating widespread exposure. Additionally, the vulnerability demonstrates poor security hygiene in software packaging practices where vendors fail to implement secure default configurations, instead relying on predictable credential schemes that are easily discovered and exploited. This flaw also impacts the principle of least privilege, as default administrative accounts should never be configured with easily guessable passwords, particularly in production environments. The vulnerability creates a persistent threat that remains active until system administrators take corrective action, and organizations must implement comprehensive credential management policies to address such configuration weaknesses.
Mitigation strategies for CVE-2016-0726 require immediate administrative action to change default passwords and implement robust credential management practices. System administrators must conduct comprehensive audits of all Nagios installations to identify affected systems and ensure that default administrative credentials are replaced with strong, unique passwords. The implementation of password policies that enforce complexity requirements and regular credential rotation should be enforced across all monitoring systems. Organizations should also consider implementing network segmentation to limit access to monitoring systems and reduce the attack surface. Regular security assessments and vulnerability scanning should be performed to identify similar misconfigurations across the infrastructure. The use of multi-factor authentication should be considered for administrative access to monitoring systems, particularly when remote access is required. Security awareness training for system administrators should emphasize the importance of changing default credentials and implementing secure configuration practices. Additionally, organizations should establish procedures for regularly reviewing and updating default configurations in deployed software packages to prevent similar issues from occurring in the future. The remediation process should include verification that the new administrative credentials are properly configured and that no other default accounts remain with predictable passwords. Regular security updates and patches should be applied to Nagios packages to address known vulnerabilities and ensure that default configurations are secure by design, rather than relying on post-installation administrative actions.