CVE-2004-0122 in Microsoft
Summary
by MITRE
Microsoft MSN Messenger 6.0 and 6.1 does not properly handle certain requests, which allows remote attackers to read arbitrary files.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 07/13/2025
Microsoft MSN Messenger versions 6.0 and 6.1 contained a critical file handling vulnerability that stemmed from improper validation of incoming data requests within the application's communication protocols. This flaw originated from a lack of proper input sanitization mechanisms that failed to adequately filter or validate file paths and request parameters received from remote peers. The vulnerability specifically manifested when the messenger application processed certain malformed or crafted requests that included malicious file path references, allowing attackers to exploit the insufficient validation controls and gain unauthorized access to arbitrary files on the target system. This represents a classic example of a buffer overflow or path traversal vulnerability that falls under the CWE-22 category for Improper Limitation of a Pathname to a Restricted Directory. The flaw existed due to inadequate boundary checking and parameter validation within the messenger's file access routines, which were designed to handle standard user communications but failed to account for maliciously crafted inputs that could bypass normal access controls.
The operational impact of this vulnerability extended beyond simple unauthorized file access, as it could potentially enable attackers to read sensitive system files, configuration data, user credentials stored in local files, or other confidential information residing on the victim's machine. Attackers could leverage this weakness to perform reconnaissance activities, gather intelligence about the target system, or escalate their access to more critical system resources. The vulnerability was particularly dangerous because it allowed remote exploitation without requiring any prior authentication or privileged access to the target system, making it a significant threat to user privacy and system security. This type of vulnerability aligns with ATT&CK technique T1005 for Data from Local System, where adversaries can access sensitive files through application-level weaknesses that bypass traditional network security controls.
The technical exploitation of this vulnerability required minimal prerequisites and could be accomplished through carefully crafted network requests that manipulated the messenger's file handling routines. Attackers needed only to establish a connection with a victim's MSN Messenger client and send a specially formatted request containing malicious file path references. The vulnerability's exploitation was further facilitated by the fact that MSN Messenger typically ran with elevated privileges on Windows systems, potentially allowing attackers to access files that would normally be restricted to system administrators. Security researchers noted that the flaw was particularly severe because it could be exploited through the messenger's peer-to-peer communication features, making it difficult to detect through traditional network monitoring approaches. Organizations using these vulnerable versions of MSN Messenger faced significant risk of data breaches, as the vulnerability could be exploited by remote attackers without any user interaction or awareness. The lack of proper access controls and input validation mechanisms meant that even legitimate users could be compromised if they received malicious requests through their contact lists or network connections. This vulnerability highlighted the importance of implementing proper security controls in instant messaging applications and demonstrated how seemingly benign communication features could be exploited for malicious purposes. Microsoft addressed this issue through security updates and patches that strengthened the input validation mechanisms and improved the file access controls within the messenger application, emphasizing the need for comprehensive security testing of communication protocols and the importance of protecting against path traversal attacks in networked applications.