CVE-2020-5866 in Controller
Summary
by MITRE
In versions of NGINX Controller prior to 3.3.0, the helper.sh script, which is used optionally in NGINX Controller to change settings, uses sensitive items as command-line arguments.
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Analysis
by VulDB Data Team • 06/02/2024
The vulnerability identified as CVE-2020-5866 affects NGINX Controller versions prior to 3.3.0 and stems from improper handling of sensitive data within the helper.sh script. This script serves as an optional utility for modifying system settings within the NGINX Controller environment, creating a potential attack surface where confidential information may be exposed through command-line arguments. The flaw represents a critical security weakness that undermines the integrity of the system's configuration management processes.
The technical implementation of this vulnerability manifests through the helper.sh script's design pattern where sensitive parameters such as passwords, API keys, or authentication tokens are passed directly as command-line arguments to system processes. This approach violates fundamental security principles by exposing confidential data in process lists and command-line interfaces accessible to unauthorized users or processes running on the same system. The script essentially transforms sensitive operational data into visible command-line parameters, creating an attack vector where malicious actors can harvest credentials through process enumeration techniques or system monitoring tools.
From an operational impact perspective, this vulnerability enables attackers to gain unauthorized access to critical system configurations and authentication credentials that should remain protected. The exposure of sensitive items through command-line arguments creates persistent security risks that can lead to complete system compromise, unauthorized access to network resources, and potential data breaches. Security researchers have identified this pattern as particularly dangerous in containerized environments or multi-tenant systems where process visibility may be increased, amplifying the potential impact of credential exposure.
The vulnerability aligns with CWE-255, which addresses the issue of insecure credential handling, and represents a direct violation of the principle of least privilege in system administration. It also maps to ATT&CK technique T1552, which covers "Unsecured Credentials" and highlights how sensitive information exposed through command-line arguments can be harvested by adversaries. Organizations using affected NGINX Controller versions face significant risk of credential compromise, especially when the helper.sh script is executed with elevated privileges or when sensitive data is processed through automated workflows.
Mitigation strategies should focus on immediate patching of affected NGINX Controller installations to version 3.3.0 or later, which contains the necessary fixes to prevent sensitive data from being passed through command-line arguments. System administrators should also implement process monitoring to detect suspicious command-line argument patterns and consider alternative credential handling mechanisms such as environment variables, secure configuration files with appropriate access controls, or direct API-based credential management. Additionally, organizations should conduct comprehensive security audits of all system scripts and utilities to identify similar vulnerabilities in credential handling practices across their infrastructure.