CVE-2000-0662 in Internet Explorer
Summary
by MITRE
Internet Explorer 5.x and Microsoft Outlook allows remote attackers to read arbitrary files by redirecting the contents of an IFRAME using the DHTML Edit Control (DHTMLED).
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Analysis
by VulDB Data Team • 04/07/2017
This vulnerability exists in internet explorer versions 5.x and microsoft outlook applications that utilize the dhtml edit control component. The flaw stems from improper input validation and access control mechanisms within the dhtml edit control which processes iframe content without adequate sanitization of file paths or uri references. Attackers can exploit this weakness by crafting malicious html content that redirects iframe contents through the dhtml edit control, enabling unauthorized file access to arbitrary locations on the target system. The vulnerability specifically leverages the control's handling of dynamic content and its interaction with local file system resources, creating a path traversal scenario where remote attackers can bypass normal file access restrictions.
The technical implementation of this vulnerability involves the manipulation of dhtml edit control's iframe redirection capabilities to access files that should normally be protected from external access. When the control processes iframe content, it fails to properly validate or sanitize the source paths, allowing attackers to specify file locations that may include relative path traversals or direct references to system files. This represents a classic case of insufficient input validation and improper access control, which aligns with common weakness enumerations such as cwe-22 path traversal and cwe-79 cross site scripting. The attack vector typically involves embedding malicious html code within email messages or web content that utilizes the dhtml edit control to process iframe references.
The operational impact of this vulnerability extends beyond simple information disclosure to potentially enable more sophisticated attacks including privilege escalation and system compromise. Remote attackers can leverage this flaw to access sensitive files such as configuration data, user credentials, or system binaries that may contain exploitable information. The vulnerability affects both email clients and web browsers, making it particularly dangerous in enterprise environments where outlook is commonly used for email communication. This creates a significant risk for organizations as attackers can target users through phishing emails containing malicious iframe content that exploits the vulnerability when the email is opened. The attack can be executed without requiring any special privileges or user interaction beyond opening the malicious content, making it particularly effective for widespread exploitation.
Mitigation strategies for this vulnerability should focus on implementing proper input sanitization and access control measures within applications that utilize the dhtml edit control. Organizations should ensure that all applications processing iframe content perform strict validation of uri references and file paths before processing. The recommended approach includes implementing proper access control lists that restrict file system access to only authorized applications and users. Additionally, security patches and updates from microsoft should be applied immediately to address the underlying vulnerability in the dhtml edit control component. Network segmentation and email filtering mechanisms can help reduce the attack surface by limiting access to potentially malicious content. From an att&ck perspective, this vulnerability maps to techniques involving privilege escalation and credential access through malicious content delivery, making it important for security teams to monitor for suspicious email activity and implement proper email security controls to prevent exploitation of this flaw.