CVE-2002-1355 in Ethereal
Summary
by MITRE
Multiple integer signedness errors in the BGP dissector in Ethereal 0.9.7 and earlier allow remote attackers to cause a denial of service (infinite loop) via malformed messages.
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Analysis
by VulDB Data Team • 06/28/2021
The vulnerability identified as CVE-2002-1355 represents a critical security flaw within the BGP dissector component of Ethereal network protocol analyzer version 0.9.7 and earlier. This issue stems from multiple integer signedness errors that occur during the processing of Border Gateway Protocol messages, which are fundamental to internet routing operations. The vulnerability specifically affects how the software handles packet length fields and other numeric values within BGP message structures, creating a scenario where malformed input can trigger unexpected behavior in the protocol analysis engine.
The technical implementation of this vulnerability involves the improper handling of signed and unsigned integer comparisons within the BGP dissector logic. When Ethereal encounters malformed BGP messages containing incorrectly sized fields or unexpected numeric values, the signedness errors cause the software to enter infinite loop conditions rather than properly handling the malformed data. This occurs because the dissector fails to validate the bounds of integer values before using them in loop control structures or array indexing operations. The flaw essentially allows an attacker to craft specially formatted BGP messages that, when processed by the vulnerable Ethereal version, cause the application to consume excessive CPU resources and become unresponsive.
From an operational impact perspective, this vulnerability creates a significant denial of service condition that can severely disrupt network monitoring and analysis operations. Network administrators relying on Ethereal for traffic inspection and debugging would experience complete service interruption when processing malicious BGP traffic, potentially leading to loss of network visibility and operational downtime. The infinite loop behavior means that the affected system remains unresponsive until manually terminated, making it particularly dangerous in automated monitoring environments where continuous operation is essential. This vulnerability directly impacts the availability aspect of the CIA triad and can be exploited by attackers to disrupt network operations without requiring authentication or privileged access.
The vulnerability maps to CWE-190, which describes integer overflow and underflow conditions, and more specifically to CWE-191, which addresses integer underflow. From an ATT&CK framework perspective, this represents a denial of service attack technique that falls under the T1499 category of Network Denial of Service, specifically targeting network infrastructure monitoring tools. The attack vector is remote and requires only the ability to send BGP messages to the target system, making it particularly dangerous in network environments where BGP traffic is commonly processed. Organizations using vulnerable versions of Ethereal should implement immediate mitigation measures including software updates, network segmentation to prevent malicious BGP traffic, and deployment of intrusion detection systems that can identify and block malformed BGP messages. The fix typically involves correcting the integer handling logic to properly validate field sizes and implement appropriate bounds checking before any loop or array operations are executed, ensuring that the dissector gracefully handles malformed input rather than entering infinite processing states.