CVE-2016-2313 in Cacti
Summary
by MITRE
auth_login.php in Cacti before 0.8.8g allows remote authenticated users who use web authentication to bypass intended access restrictions by logging in as a user not in the cacti database.
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Analysis
by VulDB Data Team • 07/24/2022
The vulnerability identified as CVE-2016-2313 affects Cacti versions prior to 0.8.8g and represents a critical authorization bypass flaw in the web authentication system. This issue specifically impacts the auth_login.php component which handles user authentication processes within the Cacti network monitoring platform. The vulnerability arises from improper validation of user credentials during the login process, allowing authenticated users to exploit a weakness in the access control mechanism.
The technical flaw stems from insufficient input validation and authentication checks within the web authentication system. When users attempt to log in through the web interface, the system fails to properly verify that the authenticated user actually exists within the Cacti database. This creates a scenario where an attacker can manipulate the authentication flow to gain access to resources that should be restricted to legitimate database users. The vulnerability is classified under CWE-285 which addresses improper authorization issues, specifically focusing on situations where access controls are bypassed through flawed authentication mechanisms.
From an operational perspective, this vulnerability poses significant risks to organizations relying on Cacti for network monitoring and management. An attacker who has obtained valid credentials for any user account within the system can exploit this flaw to access restricted monitoring data, modify configurations, or potentially escalate privileges to gain unauthorized access to network infrastructure. The impact extends beyond simple data exposure as it undermines the fundamental security model of the application, potentially allowing lateral movement within the network monitoring environment.
The attack vector requires that the attacker already possesses valid credentials for a user account within the system, but this initial requirement makes the vulnerability particularly dangerous as it can be exploited by insiders or compromised accounts. The vulnerability aligns with ATT&CK technique T1078 which covers valid accounts as a means of gaining access to systems. Organizations using Cacti versions prior to 0.8.8g should immediately implement mitigation strategies including upgrading to the patched version, implementing additional access controls, and monitoring for suspicious authentication patterns. Network segmentation and multi-factor authentication should also be considered as additional protective measures to reduce the potential impact of such authentication bypass vulnerabilities.
This vulnerability demonstrates the critical importance of proper input validation and authentication flow design in web applications. The flaw highlights how seemingly minor validation gaps can result in significant security breaches, particularly in monitoring and management systems where access to sensitive network data is common. Organizations should conduct regular security assessments of their monitoring tools and ensure timely patch management to prevent exploitation of known vulnerabilities. The incident underscores the necessity of robust authentication mechanisms and proper authorization checks that validate user identities against established databases rather than relying on potentially flawed assumptions about user legitimacy.