CVE-2012-5456 in Zoner AntiVirus Free
Summary
by MITRE
The Zoner AntiVirus Free application for Android does not verify that the server hostname matches a domain name in the subject s Common Name (CN) field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate, as demonstrated by a server used for updating virus signature files.
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Analysis
by VulDB Data Team • 02/05/2018
The vulnerability identified as CVE-2012-5456 represents a critical SSL certificate validation flaw in the Zoner AntiVirus Free Android application. This weakness stems from improper implementation of SSL/TLS certificate verification mechanisms within the mobile security software, creating a significant attack surface that adversaries can exploit to compromise the application's security integrity. The vulnerability specifically affects the certificate hostname validation process, which is a fundamental security control designed to prevent man-in-the-middle attacks by ensuring that communications occur with the intended server rather than an impostor.
The technical flaw manifests in the application's failure to properly validate that the server hostname matches the domain name specified in the Common Name field of X.509 certificates. This validation step is mandated by standard security protocols and represents a core component of the SSL/TLS handshake process. When this validation is omitted or incorrectly implemented, attackers can generate valid certificates for arbitrary domains and successfully impersonate legitimate servers during communication sessions. The vulnerability is particularly dangerous because it affects the application's ability to securely update virus signature files, which are critical for maintaining the software's effectiveness against malware threats.
This vulnerability directly enables man-in-the-middle attacks by allowing attackers to establish fraudulent SSL connections that appear legitimate to the vulnerable Android application. The impact extends beyond simple data interception, as the attacker can modify or replace legitimate virus signature files with malicious content, potentially rendering the antivirus software ineffective or even introducing new malware into the system. The attack vector is particularly concerning because it targets the very functionality that users rely on for security protection, creating a paradox where the security tool becomes a potential attack vector itself. This flaw represents a failure in the application's secure communication implementation and violates fundamental security principles outlined in industry standards.
The operational impact of this vulnerability is severe for both individual users and enterprise environments that may deploy the affected application. Users face potential exposure to malware through compromised signature updates, while organizations using the application for mobile device management may experience security breaches that could compromise their entire mobile device ecosystem. The vulnerability's persistence means that once exploited, it can remain undetected for extended periods, allowing attackers to maintain access to systems and continue compromising security. This type of flaw is classified under CWE-295, which specifically addresses "Improper Certificate Validation" and is commonly referenced in security frameworks such as the OWASP Mobile Top 10 and NIST Mobile Security Guidelines. The vulnerability aligns with ATT&CK technique T1059.007, which covers "Command and Scripting Interpreter: PowerShell" and similar execution methods, though in this case the attack vector is more specifically related to network protocol manipulation and certificate spoofing.
Mitigation strategies for this vulnerability require immediate attention from both developers and security administrators. Application developers must implement proper SSL certificate hostname validation by ensuring that the server hostname matches the certificate's Common Name field or Subject Alternative Name fields. This involves updating the application's SSL/TLS implementation to properly validate certificate chains and reject certificates that fail hostname verification. Security administrators should monitor for any signs of compromise in systems using the affected application and consider implementing network-level monitoring to detect anomalous certificate behavior. The vulnerability underscores the importance of proper secure coding practices and adherence to security standards such as those defined in the ISO/IEC 27001 framework. Organizations should also consider implementing additional security controls such as certificate pinning to provide defense in depth against similar vulnerabilities. Regular security assessments and code reviews focusing on SSL/TLS implementation are essential to prevent similar flaws from occurring in future versions of mobile security applications.