CVE-2004-0504 in Ethereal
Summary
by MITRE
Ethereal 0.10.3 allows remote attackers to cause a denial of service (crash) via certain SIP messages between Hotsip servers and clients.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 09/02/2019
The vulnerability identified as CVE-2004-0504 affects Ethereal version 0.10.3, a network protocol analyzer that was widely used for debugging and monitoring network traffic. This particular flaw manifests as a remote denial of service condition that can be triggered by sending specially crafted SIP messages to Hotsip servers and clients. The vulnerability represents a classic buffer over-read scenario where the protocol analyzer fails to properly validate input data from SIP communications, leading to a crash of the monitoring application. The issue stems from the application's insufficient handling of malformed or unexpected SIP message structures that occur during VoIP communications between Hotsip components.
The technical exploitation of this vulnerability occurs when Ethereal processes SIP messages that contain malformed data structures or unexpected field values within the SIP protocol headers. When the application attempts to parse these malformed messages, it reads beyond allocated memory boundaries or accesses invalid memory locations, causing the application to terminate abruptly. This behavior aligns with CWE-125, which describes out-of-bounds read vulnerabilities, and represents a fundamental flaw in input validation and memory management within the protocol analyzer's SIP message parsing routines. The vulnerability is particularly concerning because it can be triggered remotely without requiring authentication or special privileges, making it an attractive target for malicious actors seeking to disrupt network monitoring operations.
From an operational perspective, the impact of this vulnerability extends beyond simple service disruption as it affects the integrity of network monitoring capabilities that organizations rely upon for security operations. When Ethereal crashes due to this vulnerability, network administrators lose visibility into SIP communications, which can mask actual security incidents or prevent proper incident response. This vulnerability directly impacts the availability of network monitoring services and can be leveraged as part of broader attack campaigns targeting VoIP infrastructure. The attack pattern follows ATT&CK technique T1498, which covers network denial of service attacks, and demonstrates how protocol analyzer applications can themselves become targets for exploitation. Organizations using Ethereal for network traffic analysis would experience complete loss of monitoring capability during the time the application is crashed, potentially allowing malicious traffic to go undetected while the system is recovering.
The mitigation strategy for this vulnerability involves immediate patching of the Ethereal application to version 0.10.4 or later, which contains the necessary fixes for proper SIP message validation. Network administrators should also implement additional monitoring to detect when the application crashes and automatically restart it to maintain network visibility. Security teams should consider implementing network segmentation and access controls to limit exposure of protocol analyzers to untrusted networks, as well as deploying intrusion detection systems that can identify and block malformed SIP traffic patterns. Organizations should also maintain up-to-date backups of their network monitoring configurations and ensure that alternative monitoring solutions are available to maintain operational continuity. The vulnerability highlights the importance of input validation in network security tools and demonstrates how even legitimate security applications can contain flaws that can be exploited by attackers to disrupt critical infrastructure monitoring functions.