CVE-2011-4853 in Plesk Panel
Summary
by MITRE
The Control Panel in Parallels Plesk Panel 10.4.4_build20111103.18 includes an RFC 1918 IP address within a web page, which allows remote attackers to obtain potentially sensitive information by reading this page, as demonstrated by smb/user/list-data/items-per-page/ and certain other files.
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Analysis
by VulDB Data Team • 01/15/2018
The vulnerability identified as CVE-2011-4853 resides within the Control Panel interface of Parallels Plesk Panel version 10.4.4_build20111103.18, representing a significant information disclosure weakness that exposes internal network infrastructure details to remote attackers. This flaw specifically manifests through the inclusion of RFC 1918 private IP address ranges within web page content, creating an unintended data leakage channel that violates fundamental security principles of network isolation and information hiding. The vulnerability affects multiple endpoints within the control panel, notably including the smb/user/list-data/items-per-page/ path and other related files, demonstrating a systemic issue in how the application handles internal network addressing information.
The technical implementation of this vulnerability stems from improper input validation and output sanitization within the Plesk Panel's web interface components. When the control panel generates web pages for user interaction, it inadvertently incorporates private IP address ranges such as 10.x.x.x, 172.16.x.x through 172.31.x.x, and 192.168.x.x into the HTML responses. This occurs because the application fails to properly filter or obfuscate internal network addressing information before rendering web content, creating a direct information disclosure vector. The inclusion of these addresses provides attackers with insights into the internal network topology, potentially revealing the structure of the hosting environment and the presence of internal services that should remain hidden from external observation. This type of information leakage directly relates to CWE-200, which covers "Information Exposure," and represents a clear violation of the principle of least privilege in information access.
The operational impact of this vulnerability extends beyond simple information disclosure, as it significantly undermines the security posture of systems running Parallels Plesk Panel. Remote attackers can leverage this information to conduct more sophisticated attacks, including network reconnaissance, service enumeration, and potentially privilege escalation attempts. The leaked IP address information enables attackers to map internal network structures, identify potential internal services, and plan targeted attacks against specific components within the hosting environment. This vulnerability particularly affects organizations that rely on Plesk for web hosting management, as it creates an entry point for threat actors to gather intelligence before launching more advanced attacks. The impact is compounded by the fact that this information disclosure occurs in standard administrative interfaces that are accessible to legitimate users, making the vulnerability difficult to detect and remediate without proper monitoring.
Security practitioners should implement several mitigation strategies to address this vulnerability effectively. The primary approach involves updating to a patched version of Parallels Plesk Panel that properly sanitizes internal IP address information from web responses. Organizations should also consider implementing network segmentation measures to isolate the control panel from critical internal systems, ensuring that even if information is leaked, the attack surface remains minimized. Additionally, web application firewalls and content filtering mechanisms can be configured to detect and block the transmission of RFC 1918 addresses in web responses, providing an additional layer of protection. From an operational perspective, regular security assessments should include monitoring for similar information disclosure vulnerabilities in web applications, particularly focusing on the handling of internal addressing information. The vulnerability demonstrates the importance of following secure coding practices and the principle of defense in depth, as highlighted in the ATT&CK framework's information gathering techniques that leverage such vulnerabilities for reconnaissance purposes. Organizations should also establish proper incident response procedures to quickly identify and remediate similar issues when they arise in other applications or systems.