CVE-2017-1000027 in SME Server
Summary
by MITRE
Koozali Foundation SME Server versions 8.x, 9.x, 10.x are vulnerable to an open URL redirect vulnerability in the user web login function resulting in unauthorized account access.
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Analysis
by VulDB Data Team • 07/17/2017
The vulnerability identified as CVE-2017-1000027 affects the Koozali Foundation SME Server across versions 8.x, 9.x, and 10.x, representing a critical security flaw in the authentication mechanism. This open URL redirect vulnerability specifically targets the user web login function, creating a pathway for malicious actors to exploit the system's authentication flow. The flaw resides in how the system handles redirect parameters during the login process, allowing attackers to manipulate the redirect URL to point to malicious destinations. This type of vulnerability falls under CWE-601, which categorizes open redirect vulnerabilities as a serious concern in web application security, as it enables attackers to redirect users to fraudulent websites while maintaining the appearance of legitimate system behavior.
The technical implementation of this vulnerability stems from inadequate input validation and sanitization within the login function's redirect parameter handling. When users attempt to log into the SME Server, the system processes a redirect URL parameter that should normally direct users back to their intended destination after authentication. However, the flawed implementation fails to properly validate or sanitize this parameter, allowing attackers to inject malicious URLs. The vulnerability specifically impacts the web-based login interface where users are redirected to a designated page after successful authentication, making it a prime target for phishing attacks and credential theft. Attackers can craft malicious URLs that appear legitimate to users while redirecting them to attacker-controlled domains.
The operational impact of this vulnerability extends beyond simple unauthorized access, creating a comprehensive threat vector that can lead to full system compromise. An attacker exploiting this vulnerability can redirect authenticated users to malicious websites designed to harvest credentials, install malware, or perform additional reconnaissance activities. The vulnerability enables a form of social engineering attack where users believe they are accessing legitimate system resources while actually being redirected to attacker-controlled domains. This creates a significant risk for organizations using SME Server, as compromised user sessions can lead to unauthorized data access, system manipulation, and potential lateral movement within the network. The open redirect allows attackers to create convincing phishing pages that appear to be legitimate system interfaces, increasing the likelihood of successful credential theft.
Organizations should implement immediate mitigations including input validation and sanitization of redirect parameters, implementing strict URL validation that only allows redirection to pre-approved domains, and employing proper authentication flow controls. The fix should involve modifying the login function to validate redirect URLs against a whitelist of trusted domains and reject any external or untrusted redirect parameters. Additionally, implementing proper session management and authentication controls can help prevent exploitation of this vulnerability. Security teams should also conduct thorough penetration testing to identify any other potential redirect vulnerabilities within the system and ensure that all web applications follow secure coding practices. The vulnerability demonstrates the importance of adhering to security standards such as those outlined in the OWASP Top Ten and NIST cybersecurity guidelines, particularly focusing on authentication and session management controls. Organizations should also consider implementing web application firewalls and monitoring for suspicious redirect patterns to detect potential exploitation attempts.