CVE-2002-2185 in Linux
Summary
by MITRE
The Internet Group Management Protocol (IGMP) allows local users to cause a denial of service via an IGMP membership report to a target s Ethernet address instead of the Multicast group address, which causes the target to stop sending reports to the router and effectively disconnect the group from the network.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 06/14/2019
The vulnerability described in CVE-2002-2185 represents a critical flaw in the Internet Group Management Protocol implementation that affects network multicast communications. This weakness resides in how IGMP handles membership reporting mechanisms, specifically within the layer 2 Ethernet addressing scheme used for multicast group management. The vulnerability allows malicious actors to exploit the protocol's trust model by crafting specially formatted IGMP membership reports that target specific Ethernet addresses rather than the intended multicast group addresses. This fundamental misalignment in addressing creates a scenario where network routers and switches interpret these malformed reports as legitimate group membership information, leading to catastrophic network disruption.
The technical exploitation of this vulnerability occurs when an attacker sends an IGMP membership report packet with a forged Ethernet destination address that points to a specific network device rather than to the multicast group address. This manipulation causes the target device to believe it has joined a multicast group, while simultaneously disrupting the legitimate multicast communication flow. The underlying flaw stems from insufficient validation of the Ethernet address in the IGMP packet structure, allowing attackers to bypass normal protocol validation checks. According to CWE-284, this represents an improper access control vulnerability where the system fails to properly validate the addressing information, and the issue aligns with ATT&CK technique T1498 which covers network denial of service attacks.
The operational impact of this vulnerability extends beyond simple service disruption to create significant network reliability issues that can affect entire multicast domains. When a router stops sending reports to the multicast group, it effectively isolates network participants from receiving multicast traffic, which can compromise critical network services such as video streaming, VoIP communications, and real-time data distribution systems. The vulnerability particularly affects networks that rely heavily on multicast routing protocols, making it a significant concern for enterprise networks, content delivery networks, and any infrastructure where multicast traffic is essential for operations. Organizations implementing the affected protocols may experience cascading failures where the initial disruption propagates through the network, potentially affecting multiple segments and services.
Mitigation strategies for this vulnerability require a multi-layered approach that addresses both the immediate protocol-level issues and broader network security controls. Network administrators should implement IGMP snooping on switches to validate multicast group membership information and prevent unauthorized devices from manipulating multicast traffic flows. The implementation of access control lists and packet filtering rules can help identify and block malformed IGMP packets based on their Ethernet address patterns. Additionally, network segmentation and monitoring solutions should be deployed to detect unusual multicast traffic patterns that may indicate exploitation attempts. Organizations should also consider implementing network intrusion detection systems that can identify anomalous IGMP behavior and alert network administrators to potential attacks. Regular protocol updates and firmware patches should be applied to ensure that network equipment implements proper validation mechanisms for IGMP packet addressing, as specified in RFC 1112 and subsequent multicast protocol standards.