CVE-2017-9567 in Mobile Banking App
Summary
by MITRE
The avb-bank-mobile-banking/id592565443 app 3.0.0 for iOS does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.
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Analysis
by VulDB Data Team • 10/18/2019
The vulnerability identified as CVE-2017-9567 affects the avb-bank-mobile-banking application version 3.0.0 for iOS operating systems, representing a critical security flaw in the mobile banking ecosystem. This issue manifests as a failure in the application's certificate validation mechanism, specifically within the SSL/TLS implementation that is fundamental to secure communications between mobile banking clients and financial servers. The vulnerability resides in the application's inability to properly validate X.509 certificates, which are essential cryptographic certificates that establish trust in secure communications. This weakness creates a pathway for malicious actors to exploit the authentication process and compromise the integrity of the banking application's secure communication channels.
The technical flaw in CVE-2017-9567 constitutes a failure in certificate pinning and validation protocols, which directly maps to CWE-295 - Improper Certificate Validation. The application's SSL/TLS implementation does not perform proper certificate chain validation, allowing attackers to present fraudulent certificates that appear legitimate to the mobile banking client. This vulnerability operates at the transport layer security level where the application should enforce strict certificate validation, including checking certificate authorities, expiration dates, and certificate signatures against trusted root certificates. The absence of this validation creates a trust relationship that can be easily manipulated by adversaries who can intercept communications and present malicious certificates that the application will accept without proper verification.
The operational impact of this vulnerability is severe and directly threatens the confidentiality and integrity of financial transactions conducted through the mobile banking application. Attackers can execute successful man-in-the-middle attacks by intercepting network traffic between the mobile device and the banking server, then presenting forged certificates that the application accepts as legitimate. This allows threat actors to eavesdrop on sensitive financial communications, capture login credentials, transaction details, account information, and potentially redirect funds through fraudulent transactions. The vulnerability affects the core security model of the mobile banking application, undermining the fundamental security assumptions that users rely upon when conducting financial transactions. This weakness particularly impacts the authentication and data protection mechanisms that are critical for maintaining user trust and regulatory compliance in financial services.
The threat landscape for CVE-2017-9567 aligns with ATT&CK technique T1046 - Network Service Scanning and T1566 - Phishing, as attackers can leverage this vulnerability to establish persistent access points for further exploitation. Organizations should implement certificate pinning mechanisms that validate against specific certificate fingerprints rather than relying solely on standard certificate chain validation. The recommended mitigations include implementing strict certificate validation procedures, enabling certificate pinning for the application, and conducting regular security assessments of mobile applications. Additionally, organizations should establish monitoring protocols to detect unusual certificate validation patterns and ensure that all mobile banking applications maintain up-to-date certificate trust stores. This vulnerability demonstrates the critical importance of proper cryptographic implementation in mobile financial applications, as highlighted by industry standards such as NIST SP 800-52 and OWASP Mobile Top 10, which emphasize the necessity of robust certificate management and validation processes in mobile banking security frameworks.