DFOH - A System to Detect Forged-Origin Hijacks

Despite global efforts to secure Internet routing, attackers still successfully exploit the lack of strong BGP security mechanisms. This paper focuses on an attack vector that is frequently used: Forged-origin hijacks, a type of BGP hijack where the attacker manipulates the AS path to make it immune to RPKI-ROV filters and appear as legitimate routing updates from a BGP monitoring standpoint. Our contribution is DFOH, a system that quickly and consistently detects forgedorigin hijacks in the whole Internet. Detecting forged-origin hijacks boils down to inferring whether the AS path in a BGP route is legitimate or has been manipulated. We demonstrate that current state-of-art approaches to detect BGP anomalies are insufficient to deal with forged-origin hijacks. We identify the key properties that make the inference of forged AS paths challenging, and design DFOH to be robust against real-world factors (e.g., data biases). Our inference pipeline includes two key ingredients: (i) a set of strategically selected features, and (ii) a training scheme adapted to topological biases. DFOH detects 90.9% of the forged-origin hijacks within only ≈5min. In addition, it only reports ≈17.5 suspicious cases every day for the whole Internet, a small number that allows operators to investigate the reported cases and take countermeasures.