CVE-2000-1150 in Felix
Summary
by MITRE
Felix IRC client in BeOS r5 pro and earlier allows remote attackers to conduct a denial of service via a message that contains a long URL.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 05/28/2018
The vulnerability identified as CVE-2000-1150 affects the Felix IRC client running on BeOS r5 pro and earlier versions, representing a classic denial of service flaw that exploits the client's handling of malformed input data. This issue demonstrates how seemingly innocuous network communication elements can be weaponized to disrupt system availability. The vulnerability specifically targets the client's message processing functionality where it encounters excessively long URLs within IRC messages, creating a condition that causes the application to crash or become unresponsive.
The technical root cause of this vulnerability lies in the absence of proper input validation within the Felix IRC client's message parsing routines. When the client receives an IRC message containing an abnormally long URL, the application fails to implement bounds checking or length limitations on the URL field. This lack of input sanitization creates a buffer overflow condition or memory exhaustion scenario that ultimately leads to application termination. The vulnerability is categorized under CWE-122 as improper restriction of operations within a limited memory buffer, though in this specific case it manifests more as a resource exhaustion issue. The flaw demonstrates poor defensive programming practices where the client assumes all incoming data will conform to expected parameters without implementing adequate validation mechanisms.
The operational impact of this vulnerability extends beyond simple service disruption as it enables remote attackers to systematically target IRC clients without requiring authentication or elevated privileges. Attackers can craft malicious IRC messages containing URLs exceeding normal length parameters and broadcast them to channels where the vulnerable Felix client is active. Once received, these messages trigger the denial of service condition causing the client to crash, forcing users to restart the application and potentially lose their connection to the IRC network. The vulnerability affects the availability aspect of the CIA triad, specifically targeting the system's ability to maintain continuous operation. This type of attack falls under the ATT&CK technique T1498 which involves resource exhaustion attacks that consume system resources and cause denial of service conditions.
Mitigation strategies for this vulnerability involve implementing input validation measures that limit URL length within IRC messages to reasonable parameters. System administrators should immediately update to newer versions of the Felix client that contain proper bounds checking and input sanitization routines. The recommended approach includes implementing maximum length restrictions on URL fields within IRC message parsing code, adding proper error handling for malformed data, and incorporating defensive programming practices such as input validation before processing. Additionally, network administrators should consider implementing intrusion detection systems that can identify and block malformed IRC messages containing excessively long URLs. The vulnerability highlights the importance of following secure coding practices as outlined in the CERT/CC secure coding guidelines, specifically addressing the need for proper input validation and bounds checking in network applications. Organizations should also consider deploying network segmentation strategies to limit the potential impact of such attacks and ensure that IRC clients are not directly exposed to untrusted networks.