CVE-2016-1866 in Salt
Summary
by MITRE
Salt 2015.8.x before 2015.8.4 does not properly handle clear messages on the minion, which allows man-in-the-middle attackers to execute arbitrary code by inserting packets into the minion-master data stream.
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Analysis
by VulDB Data Team • 10/11/2024
The vulnerability described in CVE-2016-1866 affects the Salt configuration management system version 2015.8.x before 2015.8.4, representing a critical security flaw that undermines the integrity of the minion-master communication channel. This issue falls under the category of man-in-the-middle attacks where an attacker can manipulate the data flow between Salt minions and masters, potentially leading to arbitrary code execution on affected systems. The vulnerability specifically relates to the improper handling of clear messages within the Salt protocol, which creates opportunities for attackers to inject malicious packets into the communication stream without proper authentication or encryption verification.
The technical flaw manifests in Salt's failure to adequately validate message integrity during the communication process between minions and masters. When minions send clear messages to masters, the system does not properly implement cryptographic verification mechanisms that would detect tampering or unauthorized modifications to the data stream. This weakness allows attackers positioned within the network to intercept legitimate communication and inject their own packets, effectively bypassing the security controls that should protect against such interference. The vulnerability is particularly dangerous because it operates at the protocol level where authentication and encryption should provide protection against such attacks.
From an operational impact perspective, this vulnerability compromises the fundamental security assumptions of Salt's distributed architecture. Attackers who successfully exploit this weakness can execute arbitrary code on minions, potentially gaining access to sensitive configuration data, system credentials, or other valuable information. The attack vector is particularly concerning because it requires minimal privileges to exploit and can be performed by attackers who have network access to the communication channel between minions and masters. This vulnerability essentially undermines the trust model that Salt relies upon for secure configuration management, making it possible for attackers to manipulate system states and configurations without detection.
The security implications extend beyond simple code execution to encompass complete compromise of the Salt infrastructure. Attackers can leverage this vulnerability to modify configuration files, inject malicious code into the system, or redirect minion communications to unauthorized masters. This represents a significant threat to enterprise environments that depend on Salt for automated system management and configuration deployment. The vulnerability aligns with CWE-310, which addresses cryptographic issues, and maps to ATT&CK technique T1071.004 for application layer protocol manipulation. Organizations using Salt in production environments face substantial risk of unauthorized access and system compromise if they do not update to versions that address this vulnerability.
Mitigation strategies for CVE-2016-1866 require immediate patching of all affected Salt installations to version 2015.8.4 or later, which contains the necessary fixes for proper message handling and integrity verification. System administrators should also implement additional network security controls including network segmentation, intrusion detection systems, and monitoring for unusual communication patterns between minions and masters. Organizations should conduct thorough security assessments of their Salt deployments to identify any potential exploitation attempts and establish proper network access controls to limit exposure to this vulnerability. The fix addresses the core cryptographic weakness in message handling and ensures that all communications between Salt components are properly authenticated and encrypted to prevent similar man-in-the-middle attacks.