CVE-2017-5200 in SaltStack Salt
Summary
by MITRE
Salt-api in SaltStack Salt before 2015.8.13, 2016.3.x before 2016.3.5, and 2016.11.x before 2016.11.2 allows arbitrary command execution on a salt-master via Salt's ssh_client.
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Analysis
by VulDB Data Team • 11/20/2019
The vulnerability identified as CVE-2017-5200 affects SaltStack Salt's salt-api component, which serves as a RESTful API interface for interacting with Salt master servers. This flaw exists in multiple versions of the SaltStack Salt distribution, specifically before 2015.8.13, 2016.3.5, and 2016.11.2, creating a critical security risk for organizations relying on Salt's remote execution capabilities. The vulnerability stems from insufficient input validation and sanitization within the ssh_client functionality that allows unauthorized command injection attacks. This issue falls under CWE-77 and CWE-94 categories, representing command injection vulnerabilities that can be exploited to execute arbitrary code on target systems. The ATT&CK framework categorizes this as a Command and Scripting Interpreter technique, specifically leveraging the ability to execute commands through legitimate system interfaces.
The technical flaw manifests when the salt-api component processes requests containing malicious input through the ssh_client functionality. Attackers can exploit this weakness by crafting specially formatted API requests that bypass normal input validation mechanisms, allowing them to inject and execute arbitrary commands on the salt-master server. The vulnerability occurs because the system fails to properly sanitize user-supplied data before passing it to underlying system commands, creating a direct path for command injection attacks. When the salt-api processes these requests, it concatenates user input directly into system execution calls without proper escaping or validation, enabling attackers to manipulate the execution flow and gain unauthorized access to system resources.
The operational impact of this vulnerability is severe and multifaceted, as it provides attackers with arbitrary command execution privileges on the salt-master server. This level of access allows threat actors to potentially escalate their privileges further within the infrastructure, access sensitive configuration data, exfiltrate information, or establish persistent backdoors. Organizations using SaltStack for infrastructure automation and configuration management face significant risks since the salt-master typically holds administrative privileges over numerous systems. The vulnerability can be exploited remotely through the RESTful API interface, making it particularly dangerous as it requires no local system access or credentials. Attackers can leverage this vulnerability to compromise entire infrastructure automation frameworks, potentially affecting hundreds or thousands of managed systems depending on the scale of SaltStack deployment.
Mitigation strategies for CVE-2017-5200 should prioritize immediate patching of affected SaltStack installations to versions 2015.8.13, 2016.3.5, or 2016.11.2 and later. Organizations should implement network segmentation to restrict access to the salt-api endpoints, limiting exposure to trusted networks only. Additional protective measures include implementing strict API access controls, enforcing authentication and authorization mechanisms, and monitoring API traffic for suspicious patterns. The principle of least privilege should be enforced by ensuring that salt-api components operate with minimal necessary permissions and that the ssh_client functionality is properly restricted. Network-based intrusion detection systems should be configured to detect anomalous command execution patterns, and regular security audits should verify that all SaltStack components are properly updated and configured according to security best practices. Organizations should also consider implementing application firewalls or API gateways to provide additional layers of protection against command injection attacks.