CVE-2000-0982 in Internet Explorer
Summary
by MITRE
Internet Explorer before 5.5 forwards cached user credentials for a secure web site to insecure pages on the same web site, which could allow remote attackers to obtain the credentials by monitoring connections to the web server, aka the "Cached Web Credentials" vulnerability.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 04/07/2017
The CVE-2000-0982 vulnerability represents a critical security flaw in Internet Explorer versions prior to 5.5 that fundamentally compromised the integrity of secure web communications. This vulnerability emerged from a fundamental design flaw in how the browser handled authentication credentials across different security contexts within the same domain. The issue specifically affected the caching mechanism that Internet Explorer employed for user authentication tokens, creating an unintended pathway for credential exposure that persisted beyond the expected security boundaries of secure connections.
The technical implementation of this vulnerability stemmed from Internet Explorer's improper handling of HTTP authentication headers and session management between secure (https) and non-secure (http) pages within the same website domain. When a user authenticated to a secure section of a website, the browser would cache the authentication credentials in memory or local storage. However, the vulnerability allowed these cached credentials to be automatically forwarded to subsequent requests made to insecure pages on the same domain, effectively breaking the security isolation that should exist between secure and non-secure content. This behavior violated fundamental web security principles and created a scenario where sensitive authentication data could be transmitted over unencrypted channels without proper authorization.
The operational impact of this vulnerability was severe and far-reaching, particularly in environments where users accessed both secure and non-secure sections of the same website. Attackers could exploit this flaw by monitoring network traffic between users and web servers, particularly when users navigated from secure to insecure pages within the same domain. The vulnerability was especially dangerous because it could be leveraged by attackers positioned in the network path between the user and the web server, requiring no special privileges or access to the target system itself. This made the attack surface extremely broad, as any user visiting a website with both secure and insecure sections could potentially have their credentials compromised, regardless of their security awareness or protective measures.
This vulnerability aligns with CWE-384, which addresses the issue of session fixation and improper session management in web applications, and represents a classic example of how browser security mechanisms can be bypassed through inadequate implementation of authentication state management. The flaw also corresponds to techniques documented in the ATT&CK framework under credential access tactics, specifically targeting the collection of credentials through network monitoring and interception. The vulnerability's exploitation demonstrates how attackers can leverage the inherent trust relationships within web browsers to perform credential harvesting attacks, making it particularly dangerous for organizations that rely on web-based authentication systems. Organizations implementing security controls needed to address this issue by ensuring proper authentication state management and by educating users about the risks of navigating between secure and insecure sections of websites. The vulnerability ultimately highlighted the importance of maintaining strict security boundaries within web applications and the critical need for proper session management across different security contexts.