CVE-2001-0149 in Internet Explorer
Summary
by MITRE
Windows Scripting Host in Internet Explorer 5.5 and earlier allows remote attackers to read arbitrary files via the GetObject Javascript function and the htmlfile ActiveX object.
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Analysis
by VulDB Data Team • 04/12/2025
The vulnerability identified as CVE-2001-0149 represents a critical security flaw within the Windows Scripting Host component of Internet Explorer versions 5.5 and earlier. This issue specifically affects the interaction between JavaScript execution and ActiveX controls, creating an exploitable condition that enables remote attackers to access arbitrary files on the target system. The vulnerability stems from insufficient input validation and access control mechanisms within the scripting environment, particularly when processing file operations through the GetObject JavaScript function combined with the htmlfile ActiveX object.
The technical exploitation of this vulnerability occurs through a specific code execution pattern that leverages the htmlfile ActiveX object to bypass normal file access restrictions. When JavaScript code executes the GetObject function with certain parameters, it can manipulate the htmlfile object to read files from the local filesystem that would normally be protected from external access. This flaw operates at the intersection of script execution and ActiveX component interaction, where the scripting host fails to properly enforce security boundaries between different file access contexts. The vulnerability is classified under CWE-264 as a permissions, privileges, and access control issue, specifically manifesting as improper access control within the scripting environment.
The operational impact of this vulnerability is significant as it allows attackers to potentially access sensitive files including configuration data, user credentials, and system information without proper authentication. Attackers can craft malicious web pages that, when viewed in vulnerable Internet Explorer versions, automatically execute the malicious script to read files from the local system. This capability enables reconnaissance activities, credential theft, and potential escalation to full system compromise. The vulnerability's remote exploitation nature makes it particularly dangerous as it requires no local system access from the attacker and can be delivered through standard web browsing activities.
Security mitigations for CVE-2001-0149 primarily focus on immediate patching and configuration changes to prevent exploitation. Microsoft released security updates that addressed the underlying scripting host vulnerabilities, and organizations should ensure all Internet Explorer installations are updated to the latest security patches. Additional protective measures include disabling ActiveX controls in Internet Explorer, implementing proper browser security zones, and using application whitelisting to prevent unauthorized script execution. From an ATT&CK perspective, this vulnerability maps to techniques involving privilege escalation through script injection and credential access through file system exploitation. Organizations should also implement network monitoring to detect suspicious file access patterns and consider deploying web application firewalls to block malicious script execution attempts. The vulnerability demonstrates the importance of proper input validation and access control enforcement in scripting environments, particularly when dealing with ActiveX components that have elevated system privileges.