CVE-2019-6157 in System X
Summary
by MITRE
In various firmware versions of Lenovo System x, the integrated management module II (IMM2)'s first failure data capture (FFDC) includes the web server's private key in the generated log file for support.
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Analysis
by VulDB Data Team • 09/06/2023
The vulnerability described in CVE-2019-6157 represents a critical security flaw within the Lenovo System x server infrastructure, specifically affecting the integrated management module II (IMM2) firmware components. This issue manifests in the first failure data capture (FFDC) functionality which is designed to collect diagnostic information for technical support purposes when system failures occur. The FFDC mechanism serves as an essential troubleshooting tool for system administrators and vendor support teams, but in this case it inadvertently exposes sensitive cryptographic material during its operation.
The technical flaw stems from improper handling of sensitive data within the FFDC process where the web server's private key gets included in generated log files without adequate protection or sanitization. This occurs during the automatic collection of system failure information that is intended to help support personnel diagnose and resolve issues. The inclusion of the private key in these support logs creates a severe exposure that violates fundamental security principles of least privilege and data protection. The private key represents a critical cryptographic asset that, when compromised, can lead to complete system compromise and unauthorized access to encrypted communications.
From an operational impact perspective, this vulnerability creates significant risk for organizations utilizing Lenovo System x servers with IMM2 firmware. The exposure of private keys in support logs means that any individual with access to these log files can potentially impersonate the server, decrypt communications, and gain unauthorized access to sensitive data. This vulnerability directly relates to CWE-312 (Sensitive Data Exposure) and CWE-310 (Cryptographic Issues) classifications, as it exposes cryptographic keys that should remain protected. The attack surface expands when considering that these support logs may be transmitted over unencrypted channels or stored in accessible locations, potentially allowing attackers to obtain the keys through various attack vectors including network interception, unauthorized system access, or compromised support environments.
The security implications extend beyond immediate compromise to include long-term credential exposure and potential lateral movement within networks. Attackers who obtain these private keys can establish persistent backdoors, perform man-in-the-middle attacks on encrypted communications, and potentially gain access to other systems that trust the compromised server. This vulnerability aligns with ATT&CK technique T1552.004 (Credentials in Files) and T1566.002 (Phishing for Information) as it represents both a credential exposure through file-based compromise and a potential vector for information gathering. Organizations should consider implementing comprehensive monitoring for unauthorized access to support log files and establish strict access controls for these sensitive diagnostic materials. The vulnerability also highlights the importance of proper data sanitization in automated diagnostic processes and demonstrates the need for robust security testing of support and diagnostic features within firmware components.