CVE-2016-4996 in Foreman
Summary
by MITRE
discovery-debug in Foreman before 6.2 when the ssh service has been enabled on discovered nodes displays the root password in plaintext in the system journal when used to log in, which allows local users with access to the system journal to obtain the root password by reading the system journal, or by clicking Logs on the console.
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Analysis
by VulDB Data Team • 10/26/2019
The vulnerability identified as CVE-2016-4996 affects Foreman versions prior to 6.2, specifically within the discovery-debug component that interfaces with SSH services on discovered nodes. This flaw represents a critical security oversight in how system logs handle sensitive authentication data, creating an exploitable condition that undermines the security posture of managed infrastructure. The vulnerability stems from improper handling of authentication credentials within the system logging mechanism, where plaintext root passwords are inadvertently written to system journals during SSH login operations. This design flaw directly violates security best practices for credential management and logging, as it exposes privileged access information to local users who possess access to system logging facilities.
The technical implementation of this vulnerability occurs when Foreman's discovery-debug functionality enables SSH service on discovered nodes and subsequently logs authentication attempts to system journals. During the login process, the system journal captures the root password in plaintext format rather than using appropriate obfuscation or sanitization techniques. This behavior creates a persistent exposure where any local user with read access to the system journal can retrieve the plaintext credentials simply by examining log files or through the web console interface's log viewing functionality. The vulnerability specifically impacts the logging mechanisms within the Linux system journal infrastructure, where authentication data flows through standard logging channels without proper sanitization.
The operational impact of this vulnerability extends beyond immediate credential compromise, as it enables attackers with local system access to escalate privileges and gain full administrative control over affected systems. The exposure occurs during legitimate SSH login operations, making it difficult to detect through normal security monitoring procedures since the logging behavior appears to be part of normal system operation. Attackers can leverage this vulnerability through various means including direct system access, shared system environments, or through compromised local accounts that have read privileges on system logs. The vulnerability affects organizations using Foreman for infrastructure management, particularly those with discovered nodes that have SSH enabled, creating a significant risk for enterprise environments where system integrity and access control are paramount.
Security mitigations for this vulnerability require immediate patching of Foreman to version 6.2 or later where the issue has been addressed through proper credential sanitization in logging mechanisms. Organizations should implement comprehensive logging hygiene practices including regular review of system journal content, implementation of log access controls, and deployment of log monitoring solutions that can detect anomalous credential exposure patterns. The fix addresses the underlying CWE-209 weakness related to exposure of sensitive information through error messages and logging, while also aligning with ATT&CK technique T1070.002 for indicator removal through log manipulation. Additional defensive measures include restricting local system journal access, implementing centralized logging solutions with proper credential filtering, and conducting regular security audits of logging configurations to prevent similar exposure scenarios. Organizations should also consider implementing privileged access management solutions to reduce the attack surface and limit local access privileges that could enable exploitation of this vulnerability.