CVE-2005-3313 in Ethereal
Summary
by MITRE
The IRC protocol dissector in Ethereal 0.10.13 allows remote attackers to cause a denial of service (infinite loop).
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Analysis
by VulDB Data Team • 12/17/2024
The vulnerability identified as CVE-2005-3313 affects the IRC protocol dissector within Ethereal version 0.10.13, representing a critical denial of service flaw that can be exploited by remote attackers to disrupt network monitoring operations. This issue stems from the packet analysis tool's inability to properly handle malformed IRC protocol data, specifically when processing certain sequence of bytes that trigger an infinite loop within the dissector logic. The affected dissector is responsible for parsing and interpreting Internet Relay Chat protocol traffic, which is commonly used for real-time communication across networks and is frequently monitored by security professionals and network administrators.
The technical implementation of this vulnerability occurs when the IRC dissector encounters specially crafted malformed packets that contain irregularities in the protocol structure or data formatting. These malformed packets cause the dissector to enter an infinite loop during the parsing process, where the software continuously processes the same data without making forward progress. This behavior typically manifests when the dissector attempts to parse IRC messages with unexpected or corrupted field structures, particularly in the message length indicators or command parameters that control the parsing loop iterations. The flaw is classified under CWE-835, which specifically addresses the issue of infinite loops in software implementations that can be triggered by malformed input data, making it a classic example of a resource exhaustion vulnerability.
The operational impact of this vulnerability extends beyond simple service disruption as it affects the reliability and availability of network monitoring infrastructure that relies on Ethereal for protocol analysis. When exploited, the infinite loop causes the application to consume excessive CPU resources and become unresponsive, effectively rendering the monitoring tool ineffective for its intended purpose. Network administrators who depend on Ethereal for troubleshooting, security analysis, or protocol debugging would experience complete loss of functionality during the attack, potentially masking other security issues or preventing timely incident response. The vulnerability is particularly concerning in environments where continuous network monitoring is critical, as it can be exploited without requiring authentication or specialized access rights, making it an attractive target for malicious actors seeking to disrupt network operations.
Mitigation strategies for this vulnerability include immediate patching of the Ethereal application to version 0.10.14 or later, which contains the necessary fixes to prevent the infinite loop condition. Organizations should also implement network segmentation and monitoring to detect unusual CPU usage patterns that might indicate exploitation attempts. Additionally, deploying intrusion detection systems that can identify and block malformed IRC protocol traffic can provide an additional layer of protection. The vulnerability demonstrates the importance of input validation in protocol dissectors and highlights the need for robust error handling mechanisms in network analysis tools. From an ATT&CK perspective, this vulnerability aligns with the technique of resource exhaustion and can be categorized under the broader category of denial of service attacks that target application-level processing logic rather than network infrastructure. Network security teams should also consider implementing automated patch management processes to ensure timely updates of network monitoring tools and prevent exploitation of similar vulnerabilities in other protocol dissectors.