CVE-2016-10131 in CodeIgniter
Summary
by MITRE
system/libraries/Email.php in CodeIgniter before 3.1.3 allows remote attackers to execute arbitrary code by leveraging control over the email->from field to insert sendmail command-line arguments.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 10/28/2022
The vulnerability identified as CVE-2016-10131 represents a critical code execution flaw within the CodeIgniter web application framework affecting versions prior to 3.1.3. This issue resides in the system/libraries/Email.php component which handles email functionality for applications built on the framework. The vulnerability stems from insufficient input validation and sanitization of the email->from field parameter, creating a path for remote attackers to inject malicious command-line arguments that get passed to the underlying sendmail utility.
The technical flaw manifests when an attacker can manipulate the email->from field to include command-line arguments that are subsequently executed by the sendmail command. This occurs because the framework fails to properly escape or validate user-controllable input before incorporating it into system commands. The vulnerability is classified as a command injection flaw and aligns with CWE-77 which specifically addresses improper neutralization of special elements used in OS commands. Attackers can leverage this weakness to execute arbitrary commands on the server with the privileges of the web application process, potentially leading to complete system compromise.
The operational impact of this vulnerability is severe as it allows remote code execution without requiring authentication or prior access to the system. An attacker can exploit this flaw by sending specially crafted email requests through the vulnerable application, causing the sendmail utility to execute malicious commands. This vulnerability directly maps to ATT&CK technique T1059.001 which covers command and scripting interpreter, specifically focusing on the execution of system commands through the use of shell interpreters. The attack surface is broad as any application using CodeIgniter's email library and accepting user input in the from field is potentially vulnerable.
Mitigation strategies for CVE-2016-10131 require immediate patching of the CodeIgniter framework to version 3.1.3 or later where the vulnerability has been addressed through proper input sanitization and validation. Organizations should also implement additional security measures including input validation at multiple layers, restricting the sendmail utility's capabilities through proper system configuration, and implementing network segmentation to limit the potential impact of successful exploitation. Security monitoring should be enhanced to detect unusual command execution patterns and abnormal email processing behavior. The vulnerability demonstrates the critical importance of proper input validation and output encoding in preventing command injection attacks, aligning with defensive security practices outlined in the OWASP Top Ten and NIST cybersecurity frameworks.