The privacy implications of stateless IPv6 addressing

Abstract

Current implementations of the Internet Protocol version 6 (IPv6) use a static value determined from the Media Access Control (MAC) address as the host portion, or interface identifier (IID), of the IPv6 address. Some implementations create the IID using the MAC unobscured, while others compute a onetime hash value involving the MAC. As a result of this deterministic address assignment, the IID of the address is the same, regardless of the network the node accesses. This IID assignment provides interested parties (whether malicious or not) with the ability to easily track a node's physical location using simple tools such as ping and traceroute. Additionally, a static IID provides a means to correlate network traffic with a specific user. This is accomplished through a combination of filtering of the static IID and traffic analysis. The serious breaches in privacy caused by a static IID should be addressed before deployment of IPv6 becomes widespread.

Privacy and Security of DHCP Unique Identifiers

“…Using a node's MAC address in the IID has serious unintended consequences to a user's privacy [6]. The observation that this addressing scheme could allow an attacker to analyze payload, packet size, and packet timing was first made in RFC 4941 [13].…”

“…SLAAC allows for nodes to configure the interface identifier (IID), or last 64 bits, of their address independently. While this method eases the burden on network administrators, the static configuration used by many common IPv6 network implementations threatens the privacy of users [6].…”

Security and privacy produced by DHCP unique identifiers

“…Using a node's MAC address in the lID has serious unintended consequences to a user's privacy [6]. The observation that this addressing scheme could allow an attacker to analyze payload, packet size, and packet timing was first made in RFC 4941 [13].…”

“…Groat et al [6] discussed the ability to geo graphically track a user and monitor and correlate their traffic using the static lID of the autoconfigured address. RFC 4941 identified this problem [13] and concluded that a non-changing interface would allow an eavesdropper to correlate unrelated information with a particular node.…”

“…SLAAC allows for nodes to configure the interface identifier (lID), or last 64 bits, of their address independently. While this method eases the burden on network administrators, the static configuration used by many common IPv6 network implementations threatens the privacy of users [6].…”