CVE-2016-6340 in QuickStart Cloud Installer
Summary
by MITRE
The kickstart file in Red Hat QuickStart Cloud Installer (QCI) forces use of MD5 passwords on deployed systems, which makes it easier for attackers to determine cleartext passwords via a brute-force attack.
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Analysis
by VulDB Data Team • 09/20/2022
The vulnerability identified as CVE-2016-6340 resides within the Red Hat QuickStart Cloud Installer (QCI) component that manages automated system deployment processes. This issue specifically affects the kickstart file functionality which is used to configure and provision target systems during cloud deployment operations. The kickstart file serves as a critical configuration mechanism that automates the installation process and system setup, making it a prime target for exploitation when security controls are inadequately implemented. The vulnerability stems from the deliberate implementation of weak cryptographic practices within the automated deployment framework, creating a persistent security weakness that impacts all systems provisioned through this installer.
The technical flaw manifests in the explicit configuration of password hashing mechanisms within the kickstart file where MD5 encryption is enforced as the default password hashing algorithm. This represents a fundamental security failure as MD5 has been widely deprecated due to its vulnerability to collision attacks and rainbow table exploitation. The implementation forces all deployed systems to utilize MD5-based password hashing regardless of system security policies or administrator preferences, effectively creating a backdoor that exposes cleartext passwords to brute-force attacks. This weakness directly violates established cryptographic best practices and security standards that mandate the use of stronger hashing algorithms such as SHA-256 or bcrypt for password storage.
The operational impact of this vulnerability extends beyond individual system compromise to affect entire cloud deployment infrastructures. Attackers can leverage the predictable MD5 hashing to significantly reduce the computational effort required to reverse-engineer passwords through precomputed hash tables and brute-force methodologies. This vulnerability creates a persistent threat vector that remains active throughout the system lifecycle, as compromised credentials can be reused across multiple systems within the deployment environment. The weakness is particularly dangerous in cloud environments where automated provisioning occurs at scale, potentially enabling attackers to gain unauthorized access to multiple systems simultaneously. This vulnerability directly maps to CWE-327 which identifies the use of weak cryptographic algorithms and CWE-759 which addresses the use of a one-way hash without salt.
Mitigation strategies for this vulnerability require immediate attention through multiple layers of security controls. The primary remediation involves updating the kickstart file configuration to enforce stronger password hashing algorithms such as SHA-512 or bcrypt implementations that incorporate proper salting mechanisms. Organizations should implement automated security scanning tools that can detect and flag the presence of MD5-based password configurations within deployment scripts and configuration files. Additionally, security policies must be updated to mandate cryptographic strength requirements for all automated deployment processes, ensuring that password hashing algorithms meet current industry standards. The implementation of these controls aligns with ATT&CK technique T1566 which covers credential access through social engineering and T1110 which addresses password cracking and brute force attacks. System administrators should also consider implementing additional authentication controls such as multi-factor authentication and privileged access management solutions to provide defense-in-depth against potential exploitation of this weakness.