CVE-2000-0812 in Java System Web Server
Summary
by MITRE
The administration module in Sun Java web server allows remote attackers to execute arbitrary commands by uploading Java code to the module and invoke the com.sun.server.http.pagecompile.jsp92.JspServlet by requesting a URL that begins with a /servlet/ tag.
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Analysis
by VulDB Data Team • 05/24/2019
The vulnerability identified as CVE-2000-0812 represents a critical remote code execution flaw within Sun Java Web Server's administration module. This security weakness stems from insufficient input validation and improper handling of Java Servlet requests, creating an exploitable pathway for remote attackers to gain unauthorized system access. The vulnerability specifically affects the server's ability to process and compile Java Server Pages, allowing malicious actors to upload and execute arbitrary code on the target system. The flaw exists in the server's interpretation of servlet requests, particularly when processing URLs that begin with the /servlet/ prefix, which triggers the execution of the JspServlet component.
The technical implementation of this vulnerability leverages the server's JspServlet class located at com.sun.server.http.pagecompile.jsp92.JspServlet, which serves as the execution point for uploaded Java code. When an attacker uploads malicious Java bytecode or JSP files to the server, the administration module processes these files through the vulnerable JspServlet, effectively bypassing normal security restrictions. This mechanism operates under the assumption that legitimate servlet requests should be processed without additional scrutiny, creating a path for malicious code execution. The vulnerability's exploitation requires minimal privileges and can be accomplished through standard HTTP requests, making it particularly dangerous in unpatched environments.
The operational impact of this vulnerability extends beyond simple code execution to encompass full system compromise and potential data breaches. Remote attackers can leverage this flaw to deploy backdoors, steal sensitive information, modify system configurations, or use the compromised server as a launch point for attacks on other systems within the network. The vulnerability affects the confidentiality, integrity, and availability of the affected system, potentially enabling attackers to establish persistent access and maintain control over the compromised server. Organizations running vulnerable versions of Sun Java Web Server face significant risk of unauthorized access, data loss, and potential regulatory compliance violations.
Mitigation strategies for this vulnerability require immediate patch application from Sun Microsystems, which addressed the issue in subsequent releases of the Java Web Server. Network administrators should implement strict access controls and firewall rules to restrict access to administrative interfaces, particularly those handling servlet processing. The principle of least privilege should be enforced by limiting the execution capabilities of the JspServlet component and disabling unnecessary servlet mappings. Additionally, organizations should deploy intrusion detection systems to monitor for suspicious servlet requests and implement regular security audits to identify potential exploitation attempts. This vulnerability aligns with CWE-74, the "Improper Neutralization of Special Elements in Output Used by a Downstream Component," and maps to ATT&CK technique T1059.007 for remote code execution through web applications. Organizations should also consider implementing application whitelisting policies and regularly updating their security monitoring tools to detect and prevent exploitation attempts targeting similar vulnerabilities in web server components.