CVE-2002-0032 in Yahoo!
Summary
by MITRE
yahoo! messenger 5001064 and earlier allows remote attackers to execute arbitrary script as other users via the addview parameter of a ymsgr uri.
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Analysis
by VulDB Data Team • 06/16/2024
The vulnerability identified as CVE-2002-0032 represents a critical cross-site scripting flaw in Yahoo! Messenger version 5.0.0.1064 and earlier versions. This security weakness resides within the application's handling of ymsgr URI schemes, specifically in the addview parameter processing mechanism. The flaw enables remote attackers to inject malicious scripts that execute with the privileges and identity of other users who interact with the crafted URI.
The technical implementation of this vulnerability stems from insufficient input validation and sanitization within the Yahoo! Messenger client application. When users encounter a specially crafted ymsgr URI containing malicious script code within the addview parameter, the application fails to properly escape or filter the input before rendering it in the user interface. This allows attackers to craft malicious URIs that, when clicked by victims, execute arbitrary code in the context of the victim's session. The vulnerability operates at the application layer and specifically targets the web browser component that processes these URI schemes, making it particularly dangerous in social engineering scenarios.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to perform a range of malicious activities including session hijacking, data theft, and privilege escalation. Since the scripts execute with the privileges of the targeted user, attackers can potentially access confidential communications, steal session cookies, or manipulate the user's contact list and messaging capabilities. The vulnerability is particularly concerning because it leverages the trust relationship that exists between users and the messaging application, making it difficult for users to distinguish between legitimate and malicious communications. This type of vulnerability falls under CWE-79 which specifically addresses cross-site scripting flaws in web applications and related systems.
Mitigation strategies for this vulnerability require immediate patching of affected Yahoo! Messenger versions, as the original vendor released updates addressing this specific flaw. Organizations should implement strict URI validation policies and educate users about the dangers of clicking untrusted links in messaging applications. Network-level defenses can include filtering of suspicious URI schemes and implementing web application firewalls that monitor for malicious script injection patterns. The ATT&CK framework categorizes this vulnerability under initial access techniques using social engineering and execution methods that leverage trusted applications. Security professionals should also consider implementing browser security policies that restrict the execution of scripts from untrusted sources and monitor for suspicious URI patterns in network traffic logs. Regular security assessments of messaging applications and their URI handling mechanisms remain essential to prevent similar vulnerabilities from emerging in modern communication platforms.