CVE-2002-1698 in MSN Messenger
Summary
by MITRE
Buffer overflow in Microsoft MSN Messenger Service 1.0 through 4.6 allows remote attackers to cause a denial of service (crash) via a long FN (font) argument in the message header.
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Analysis
by VulDB Data Team • 06/28/2021
The vulnerability identified as CVE-2002-1698 represents a classic buffer overflow flaw within Microsoft MSN Messenger Service versions 1.0 through 4.6. This security weakness specifically targets the handling of font name arguments within message headers, creating a condition where maliciously crafted input can trigger system instability. The vulnerability operates at the application layer of the network stack, exploiting improper input validation mechanisms that fail to properly sanitize or limit the length of font parameters. According to CWE-121, this vulnerability falls under the category of stack-based buffer overflow, where insufficient bounds checking allows an attacker to write beyond allocated memory boundaries.
The technical implementation of this flaw involves the MSN Messenger Service's parsing of incoming message headers, particularly focusing on the FN parameter that specifies font information. When a remote attacker sends a message containing an excessively long font name string, the service fails to validate the input length against predefined buffer limits. This allows the malicious input to overwrite adjacent memory locations, potentially causing the service to crash or behave unpredictably. The vulnerability demonstrates characteristics consistent with CWE-787, which describes out-of-bounds write conditions that can lead to arbitrary code execution or system instability. The attack vector requires no authentication and can be executed remotely, making it particularly dangerous in networked environments where MSN Messenger services are accessible.
The operational impact of this vulnerability extends beyond simple denial of service, as it can potentially be exploited to disrupt communication services for legitimate users. When the MSN Messenger Service crashes due to buffer overflow, it creates a cascading effect that can affect network availability and user productivity. The vulnerability affects a broad range of Microsoft Messenger versions, indicating a widespread exposure across different service implementations. From an ATT&CK framework perspective, this vulnerability maps to T1499.004 which covers network denial of service attacks, and T1059 which encompasses command and scripting interpreters. The attack can be classified as a remote exploitation technique that leverages protocol parsing weaknesses to achieve service disruption.
Mitigation strategies for CVE-2002-1698 should focus on immediate patch deployment and input validation improvements. Microsoft released security updates to address this vulnerability, and system administrators should prioritize applying these patches to all affected MSN Messenger Service installations. Network segmentation and firewall rules can provide additional protection by limiting access to MSN Messenger services to trusted networks only. Implementing proper input validation mechanisms within the application code, including length checking for font parameters and other message header fields, can prevent similar vulnerabilities from occurring in future implementations. Organizations should also consider implementing intrusion detection systems that can monitor for suspicious message patterns and potential exploitation attempts. The vulnerability serves as a reminder of the critical importance of input validation and proper memory management in preventing buffer overflow attacks that can lead to system compromise or service disruption.