CVE-2014-4966: 
Ansible vulnerability analysis and mitigation

Ansible before version 1.6.7 contains multiple security vulnerabilities identified as CVE-2014-4966. The vulnerability allows remote attackers to execute arbitrary code through inventory data containing '{{' and 'lookup' substrings, and remote data with '{{' substrings. This vulnerability specifically affects the way Ansible handles data processing and input validation (OCERT Advisory).

The vulnerability involves two main issues: First, the escalation of local permission access level into arbitrary code execution, which can be triggered by interpolation of file names maliciously crafted as lookup plugin commands in combination with its pipe feature. Second, unsafe parsing of action arguments when an attacker controls variable data (including fact data, with_fileglob data, or other sources), allowing attackers to supply their own options to an action. The vulnerability has received a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (NVD).

The impact of this vulnerability is severe as it allows attackers to execute arbitrary code. For specific actions like copy or template, attackers controlling variables could trigger arbitrary code execution in addition to information leakage via the validate option's acceptance of arbitrary shell code (OCERT Advisory).

The vulnerability can be exploited when an attacker has control over certain playbook variables. The exploitation requires the ability to manipulate inventory data or remote data containing specific substrings. The vulnerability was fixed in Ansible version 1.6.7 (OCERT Advisory).

The primary mitigation is to upgrade Ansible to version 1.6.7 or later. The fix includes stripping lookup calls out of inventory variables, cleaning unsafe data returned from lookup plugins, and ensuring variables don't insert extra parameters into module args (GitHub Patch).