CVE-2014-3248 in Puppet
Summary
by MITRE
Untrusted search path vulnerability in Puppet Enterprise 2.8 before 2.8.7, Puppet before 2.7.26 and 3.x before 3.6.2, Facter 1.6.x and 2.x before 2.0.2, Hiera before 1.3.4, and Mcollective before 2.5.2, when running with Ruby 1.9.1 or earlier, allows local users to gain privileges via a Trojan horse file in the current working directory, as demonstrated using (1) rubygems/defaults/operating_system.rb, (2) Win32API.rb, (3) Win32API.so, (4) safe_yaml.rb, (5) safe_yaml/deep.rb, or (6) safe_yaml/deep.so; or (7) operatingsystem.rb, (8) operatingsystem.so, (9) osfamily.rb, or (10) osfamily.so in puppet/confine.
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Analysis
by VulDB Data Team • 04/04/2022
This vulnerability represents a classic untrusted search path flaw that affects multiple components within the puppet ecosystem including puppet enterprise, puppet itself, facter, hiera, and mcollective. The issue occurs specifically when these tools are executed with ruby 1.9.1 or earlier versions where the ruby interpreter searches for required libraries in the current working directory before checking standard system paths. This behavior creates an exploitable condition where a local attacker can place malicious files with the same names as legitimate system libraries in the current working directory, causing the application to load and execute the attacker-controlled code instead of the intended system libraries.
The technical exploitation involves placing Trojan horse files in the current working directory during execution, leveraging the ruby interpreter's search order which prioritizes local directories over system paths. Attackers can target specific library files such as rubygems/defaults/operating_system.rb, Win32API.rb, safe_yaml.rb, and various .so files that are loaded during normal operation. The vulnerability is particularly dangerous because it can be exploited without requiring elevated privileges initially, potentially allowing attackers to escalate their privileges through the execution of malicious code with the privileges of the running process.
The operational impact of this vulnerability extends beyond simple privilege escalation as it affects core infrastructure management tools used in enterprise environments. When exploited, the vulnerability can allow attackers to execute arbitrary code with the privileges of the puppet processes, potentially leading to complete system compromise or unauthorized access to configuration management systems. This is particularly concerning in enterprise settings where puppet is commonly used for managing large numbers of systems, as exploitation could provide attackers with access to entire infrastructure management capabilities. The vulnerability affects multiple versions of critical infrastructure components, making it a widespread concern across various deployments.
Mitigation strategies should focus on several key areas including immediate patching of all affected versions to the latest releases that address the search path issue. Organizations should also implement strict directory permissions and execute processes from secure working directories that do not contain user-controllable content. System administrators should consider implementing application whitelisting policies to prevent execution of unauthorized libraries and ensure that ruby 1.9.1 is upgraded to a more recent version that handles library loading more securely. Additionally, security monitoring should be enhanced to detect suspicious file creation patterns in directories where puppet processes execute, and network segmentation should be implemented to limit the potential impact of successful exploitation. This vulnerability aligns with CWE-427 Uncontrolled Search Path Element and can be mapped to ATT&CK technique T1059 Command and Scripting Interpreter for privilege escalation and code execution.