Dennis Beard Sandra Murphy Yi Yang March 2003 Threats to Routing Protocols

Outline Scope Routing Functions Threat Definition Threat Source, Action & Consequence Generally Identifiable Routing Threat Actions Threats against Multicast Routing Protocols

Scope All routing protocols Intent: advise routing protocol designers about security get them thinking about vulnerabilities set requirements (MUST, SHOULD, MAY) Intra- and Inter-domain (IGP and EGP) Security of the protocol, not of the operational environment it works in

Routing Functions Transport subsystem the subsystem that carries the data between routers can be attacked - impact on routing protocol can carry attack to the routing protocol Neighbor state determine peer and establish relationship attacks can break relationship - disrupt routing [typo: draft said BGP and CEASE msg]

Routing Functions (cont) Database maintenance sometimes a separate step, sometimes an implicit result of the communication of topology info like wireless keeping interesting routes topology computation from database Each function has control and data parts different consequences from each

Threat definition “A potential for violation of security, which exists when there is a circumstance, capability, action, or event that could breach security and cause harm.” Robert Shirey, RFC2828: Internet Security Glossary The RFC definitions are the basis for the expression of our model

Threat Model - Sources Intruders or malicious programs launched by the intruder  Compromised (or subverted??) links  Compromised (or subverted??) routers  Masquerading routers (illegitimately assumes identity/ role)  Unauthorized devices  Should RP designers worry about subverted links?  Should we distinguish masquerading from unauthorized routers? * A router may play multiple roles simultaneously

Threat Model - Actions Attacks and other intentional malicious actions against the routing protocols Address proper protocol design to mitigate threat Need to identify external factor that protocol should protect  Deliberate exposure  Sniffing/ wiretapping  Traffic analysis  Spoofing  Falsification  Interference  Overload * An attacker may launch multiple actions simultaneously

Threat Model - Consequences Compromises and the damage done by the malicious actions Zones (impact to router(s), Autonomous System(s), Global) Period (smaller, equal or greater than threat action duration)  Disclosure Unauthorized access to routing info  Deception Belief of false routing info  Disruption Operation degradation or interruption  Usurpation Control/ modification of legitimate router services / functions * An action may cause multiple consequences

Deliberate Exposure Intentional release of routing information Sniffing Monitor routing exchange between legitimate routers Traffic Analysis Indirect access to routing info gained by monitoring data traffic Spoofing Assume other’s identity Falsification Declare invalid routing information Interference Impact routing exchanges Overload Place excessive burdens Generally Identifiable Threat Actions

Deliberate Exposure Intentional release of routing information to unauthorized devices All attackers Disclosure Is this a valid threat against routing protocols?

Sniffing/ Wiretapping Monitor / record routing information Compromised / subverted links Disclosure

Traffic Analysis Analyze data traffic to learn routing information Compromised / subverted links Disclosure Is this a valid threat against routing protocols?

Spoof Illegally assumes a legitimate router's identity All attackers Attackers become masquerading routers after successful spoof It is a threat, as well as a means to launch threat Consequences: Deception (on peer relationship) and Dos based on the Deception Accounting Disclosure (on routing information)

Falsification Make and distribute invalid routing information Sources: Originator: All attackers except compromised / subverted links Overclaiming Underclaiming Misclaiming Is underclaiming a valid threat? (not-existing vs. not defendable) Forwarder: all attackers Overstatement Understatement Misstatement

Falsification (cont) Consequences: Deception Usurpation Disruption

Interference Inhibit routing exchanges All attackers Disruption

Overload Place excess burden Against control plane or data plane Should we care about data plane in routing protocol design? All attackers Disruption

Byzantine Failures Caused by faulty routers So general that redundant to other threat actions: falsification, overload… Should not be listed separately

Discarding of control packets Similar to underclaiming? OLSR

Network Mapping Threats Threat action or consequence? If this is action, is it redundant to sniffing/traffic analysis?

Multicast Routing Threat Actions Introduction of misleading route information via non- existent (black hole) or incorrect routes is a key MC routing vulnerability MC routing protocols are at least as susceptible as Unicast. Updates can be: Fabricated Modified Replayed Deleted Snooped

Sandy’s Comments Summarized Section 3.1: content Section 4.1: Deliberate Exposure: content Section 4.3: Traffic Analysis: content Section 4.4: Spoofing: editorial Section 4.5: Underclaiming: content Section 4.5a: “ownership”: editorial Section 4.7: Overload: editorial/content Section 4.8: Byzantine Failures: editorial Section 4.9: Discard of Control Messages: content Section 4.10: Network Mapping: editorial Multicast Routing: editorial (redundant, inconsistent)

Sandy’s Comments: Some Themes privacy of routing data - important? comments both ways on mailing list nemo group wants “location privacy” Section 4.1: Deliberate Exposure Section 4.3: Traffic Analysis not attack in routing protocol (or not addressable) Section 4.3: Traffic Analysis Section 4.7: Overload Section 2: Transport Subsystem correctness vs security Section 4.5: Underclaiming Section 4.9: Discard of Control messages

Sanity Checks Need to compare to BGP Attack Tree document see if there are attacks there not represented here and vice versa many of that document’s attacks are operational in nature (I.e., not the business of this analysis) Need to compare to SOBGP/SBGP see if those approaches deal with these threat actions, sources, consequences see if there are any further vulnerabilities unprotected Need to compare to other routing protocol expressed security requirements (e.g., nemo)

In Closing… We have presented a model to: Document threats & related consequences Provide a format to help prioritize results Enable a process to: 1. Address top threat actions 2. Make a decision on medium/ low threat actions Must be included Acceptable risk (future work)

Next Step Need your input to address the following: Structure Content Thank You!