CVE-2011-5242 in tmhOAuth
Summary
by MITRE
tmhOAuth before 0.61 does not verify that the server hostname matches a domain name in the subject s Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.
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Analysis
by VulDB Data Team • 02/23/2019
The vulnerability described in CVE-2011-5242 affects the tmhOAuth library version 0.60 and earlier, representing a critical security flaw in SSL/TLS certificate verification mechanisms. This issue resides in the library's handling of X.509 certificates during secure communications, specifically failing to validate that the server hostname matches either the Common Name field or Subject Alternative Name fields within the certificate. The absence of this validation creates a significant gap in the library's security posture, allowing malicious actors to exploit the system through man-in-the-middle attacks.
The technical flaw manifests in the library's certificate validation process where it accepts any valid SSL certificate without proper hostname verification. This behavior directly violates established security protocols and industry standards such as CWE-295, which addresses improper certificate validation. The vulnerability enables attackers to present any valid certificate, regardless of whether it corresponds to the intended server, effectively breaking the trust model that SSL/TLS is designed to establish. This weakness operates at the core of secure communication protocols, undermining the fundamental security guarantee that certificates provide.
From an operational impact perspective, this vulnerability creates a severe risk for applications using the affected tmhOAuth library, particularly those handling sensitive data or authentication processes. Attackers can intercept communications, steal session cookies, access user credentials, and perform unauthorized data manipulation. The attack vector is particularly dangerous because it requires minimal technical expertise to exploit, making it attractive to threat actors across different skill levels. Organizations relying on this library for OAuth implementations face potential data breaches, identity theft, and compliance violations that could result in significant financial and reputational damage.
The vulnerability aligns with several ATT&CK techniques including T1566 for credential access through spoofed certificates and T1046 for network service scanning that could lead to certificate manipulation. Mitigation strategies should focus on immediate library updates to version 0.61 or later where proper hostname verification has been implemented. Organizations must also conduct comprehensive audits of their codebases to identify all instances where this library is used, implement additional monitoring for suspicious certificate behavior, and consider deploying certificate pinning mechanisms as an additional layer of protection. Security teams should also review their network traffic analysis tools to detect potential man-in-the-middle activities that could indicate exploitation attempts. The fix addresses the core issue by implementing proper SSL certificate hostname verification, ensuring that server certificates match the expected domain names through validation of both the Common Name and Subject Alternative Name fields as required by industry best practices and security standards.