CVE-2011-4746 in Plesk Panel
Summary
by MITRE
The billing system for Parallels Plesk Panel 10.3.1_build1013110726.09 does not disable the SSL 2.0 protocol, which makes it easier for remote attackers to conduct spoofing attacks by leveraging protocol weaknesses.
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Analysis
by VulDB Data Team • 01/23/2018
The vulnerability identified as CVE-2011-4746 affects the billing system component of Parallels Plesk Panel version 10.3.1_build1013110726.09, representing a critical security flaw in the cryptographic protocol implementation. This issue stems from the failure to disable the SSL 2.0 protocol within the billing system's SSL configuration, creating an exploitable weakness that significantly undermines the security posture of affected systems. The vulnerability resides in the server-side cryptographic configuration rather than application logic flaws, making it particularly concerning for environments where financial transactions and sensitive billing data are processed. According to the CWE taxonomy, this corresponds to CWE-319: Cleartext Transmission of Sensitive Information, as the vulnerability enables attackers to potentially intercept and manipulate data transmitted through insecure protocols. The specific implementation flaw involves the absence of proper SSL protocol version restrictions within the billing system's configuration, allowing legacy and insecure SSL 2.0 connections to persist despite being deprecated due to known security vulnerabilities.
The operational impact of this vulnerability extends beyond simple protocol misconfiguration, as it creates opportunities for sophisticated man-in-the-middle attacks and session hijacking attempts. Remote attackers can exploit the SSL 2.0 protocol's inherent weaknesses to perform protocol downgrade attacks, forcing connections to use the insecure SSL 2.0 implementation instead of more secure protocols like TLS 1.0 or higher. This vulnerability directly maps to ATT&CK technique T1071.004: Application Layer Protocol: DNS, where attackers may leverage weakened cryptographic layers to establish unauthorized communication channels. The billing system's exposure to such attacks creates a significant risk for organizations managing customer financial data, as SSL 2.0 is vulnerable to several known cryptographic attacks including the FREAK vulnerability and issues with weak key exchange mechanisms. The presence of SSL 2.0 support in the billing system effectively provides an attack vector that bypasses modern security controls, making it easier for threat actors to conduct successful spoofing attacks against the system.
Organizations affected by this vulnerability face substantial risk exposure, particularly in environments where the billing system processes sensitive customer information or handles financial transactions. The flaw creates an insecure communication channel that can be exploited to intercept transaction data, manipulate billing information, or conduct unauthorized access attempts against the billing system. Security professionals should note that SSL 2.0 has been deprecated since 2011 due to fundamental cryptographic weaknesses and is no longer recommended for any production use. The vulnerability's persistence in Plesk Panel 10.3.1_build1013110726.09 demonstrates a failure in proper security configuration management and highlights the importance of maintaining up-to-date security practices. Organizations should implement immediate remediation measures including disabling SSL 2.0 support through configuration changes, updating to newer versions of Plesk Panel that properly enforce secure protocol usage, and conducting comprehensive security audits of all SSL/TLS configurations within their infrastructure. The remediation process should align with industry best practices outlined in NIST SP 800-52 and RFC 7525, which specifically recommend disabling support for insecure SSL protocols and enforcing the use of modern TLS implementations to prevent downgrade attacks and cryptographic vulnerabilities.