CVE-2006-1644 in Interact
Summary
by MITRE
login.php in Interact 2.1.1 generates different responses depending on whether or not a username is valid, which allows remote attackers to determine valid usernames. NOTE: the provenance of this information is unknown; the details are obtained solely from third party information.
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Analysis
by VulDB Data Team • 07/22/2018
The vulnerability identified as CVE-2006-1644 affects the login.php component of Interact version 2.1.1, presenting a significant security weakness that enables remote attackers to enumerate valid usernames through differential response analysis. This issue stems from the application's failure to provide consistent error messaging regardless of whether a username exists in the system. When an attacker submits a login request with a non-existent username, the application returns a different response compared to when a valid username is provided but an incorrect password is submitted. This behavioral inconsistency creates a predictable pattern that adversaries can exploit to systematically identify legitimate user accounts within the system.
The technical flaw represents a classic case of information disclosure through response differentiation, which aligns with CWE-204, Information Exposure Through Response Difference. The vulnerability operates at the authentication layer where the system should maintain uniform response behavior to prevent attackers from distinguishing between valid and invalid usernames. This weakness directly violates security principles of consistent error handling and proper access control implementation. The attack vector is classified as remote and requires no authentication to exploit, making it particularly dangerous as it can be executed from any network location without prior system access.
The operational impact of this vulnerability extends beyond simple username enumeration, as it provides attackers with a foundational foothold for more sophisticated attacks. Once valid usernames are identified, attackers can proceed with password spraying, brute force attacks, or social engineering campaigns targeting specific user accounts. The vulnerability affects the authentication security model by weakening the system's ability to maintain confidentiality of user account information. This weakness can be leveraged in conjunction with other attack techniques, potentially leading to unauthorized system access, privilege escalation, and data breaches. The vulnerability also impacts the principle of least privilege by exposing user account information that should remain confidential until authenticated access is achieved.
Mitigation strategies should focus on implementing consistent error handling throughout the authentication process to ensure that all login attempts return identical responses regardless of username validity. The system should be configured to provide generic error messages such as "Invalid username or password" for all authentication failures, preventing attackers from distinguishing between valid and invalid account names. Security measures should include rate limiting and account lockout mechanisms to prevent automated enumeration attempts, while also implementing proper logging and monitoring to detect suspicious login patterns. Organizations should conduct regular security assessments to identify similar vulnerabilities in authentication systems and ensure compliance with security standards such as those outlined in the NIST Cybersecurity Framework. The remediation process involves modifying the login.php script to normalize error responses and implementing additional layers of authentication security to prevent exploitation of similar information disclosure vulnerabilities.