CVE-2009-5147 in Ruby
Summary
by MITRE
DL::dlopen in Ruby 1.8, 1.9.0, 1.9.2, 1.9.3, 2.0.0 before patchlevel 648, and 2.1 before 2.1.8 opens libraries with tainted names.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 11/24/2022
The vulnerability described in CVE-2009-5147 represents a critical security flaw in the Ruby programming language's dynamic loading mechanism. This issue affects multiple versions of Ruby including 1.8, 1.9.0, 1.9.2, 1.9.3, 2.0.0 before patchlevel 648, and 2.1 before 2.1.8, where the DL::dlopen function fails to properly validate library names before attempting to load them into memory. The core technical flaw stems from the improper handling of tainted input within the dynamic loading process, creating a potential pathway for malicious code execution through carefully crafted library names.
The operational impact of this vulnerability is significant as it allows attackers to exploit the tainted name handling mechanism to load arbitrary shared libraries with elevated privileges. When Ruby processes library names that have been marked as tainted, typically due to user input or external data sources, the DL::dlopen function does not adequately sanitize these inputs before attempting to load the specified libraries. This behavior creates a direct attack surface where malicious actors can manipulate the library loading process to execute code in the context of the running Ruby application. The vulnerability aligns with CWE-776, which addresses improper input validation in dynamic loading scenarios, and can be mapped to ATT&CK technique T1059.007 for dynamic code injection through shared library loading.
The security implications extend beyond simple code execution as this vulnerability can be leveraged in various attack vectors including web application exploitation, where user-controllable input flows through Ruby's dynamic loading mechanisms. Attackers can craft malicious library names that, when processed by DL::dlopen, result in the loading of attacker-controlled shared libraries from arbitrary locations on the filesystem. This creates opportunities for privilege escalation attacks, especially when Ruby applications run with elevated permissions or are used in server environments where shared library paths may be manipulated. The vulnerability particularly affects applications that dynamically load libraries based on user input or configuration data, making it a widespread concern across Ruby-based systems. Organizations should implement immediate mitigations including patching affected Ruby versions, implementing proper input validation for dynamic loading operations, and restricting library loading permissions to prevent unauthorized code execution through this vector.