CVE-2002-0593 in Navigator
Summary
by MITRE
Buffer overflow in Netscape 6 and Mozilla 1.0 RC1 and earlier allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a long channel name in an IRC URI.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 05/29/2019
The vulnerability identified as CVE-2002-0593 represents a critical buffer overflow flaw affecting Netscape 6 and Mozilla 1.0 RC1 web browsers and earlier versions. This security issue stems from inadequate input validation within the browser's handling of IRC (Internet Relay Chat) URIs, specifically when processing channel names that exceed predetermined buffer limits. The flaw occurs during the parsing of IRC protocol identifiers that contain channel specifications, where the application fails to properly constrain the length of channel names before storing them in fixed-size memory buffers. This oversight creates an exploitable condition that can be triggered by maliciously crafted IRC URIs containing excessively long channel identifiers.
The technical implementation of this vulnerability manifests through improper bounds checking during URI parsing operations. When the browser encounters an IRC URI with an extended channel name, the application attempts to store this data in a predetermined memory buffer without validating whether the input exceeds the allocated space. This results in memory corruption that can overwrite adjacent memory locations, potentially leading to unpredictable behavior including application crashes or more severe exploitation outcomes. The buffer overflow occurs in the context of the browser's protocol handler for IRC connections, making it accessible through web pages or email links that contain maliciously formatted IRC URIs.
From an operational perspective, this vulnerability presents significant risks to users of affected browser versions, as exploitation can lead to both denial of service conditions and potential remote code execution. The denial of service aspect manifests as application crashes and system instability when users encounter maliciously crafted IRC URIs, while the remote code execution capability represents a more severe threat that could allow attackers to gain control over affected systems. The vulnerability is particularly concerning because it can be triggered through legitimate web browsing activities, requiring no special privileges or user interaction beyond visiting a malicious website or clicking a link. Attackers can leverage this flaw to deliver payloads that exploit the buffer overflow condition, potentially executing arbitrary code with the privileges of the affected browser process.
Mitigation strategies for CVE-2002-0593 focus primarily on immediate remediation through software updates and patches provided by the vendors. Users should immediately upgrade to patched versions of Netscape 6 and Mozilla 1.0, which include proper input validation and bounds checking mechanisms for IRC URI processing. Organizations should implement network-based controls such as URL filtering and web proxy configurations to block access to potentially malicious IRC URIs until full patch deployment is complete. Additionally, browser security configurations should be hardened by disabling IRC protocol handlers or implementing strict input validation for all URI schemes. This vulnerability aligns with CWE-121, which describes heap-based buffer overflow conditions, and demonstrates characteristics consistent with attack patterns found in the MITRE ATT&CK framework under the technique of "Exploitation for Privilege Escalation" and "Command and Scripting Interpreter". The vulnerability underscores the importance of proper input validation in protocol handlers and demonstrates how seemingly benign URI parsing operations can become significant security risks when adequate bounds checking is absent.