Amazon recently lost control of IP addresses it uses to host cloud services and took more than three hours to regain control, a lapse that allowed hackers to steal $235,000 in cryptocurrency from users of one of the affected customers, an analysis shows.
The hackers seized control of roughly 212 IP addresses through BGP hijacking, a form of attack that exploits known weaknesses in a core Internet protocol. Short for border gateway protocol, BGP is a technical specification that large network operators, known as autonomous system networks, use to interoperate with other ASNs. Despite its crucial function in routing wholesale amounts of data across the globe in real time, BGP still largely relies on the Internet equivalent of word of mouth for organizations to track which IP addresses rightfully belong to which ASNs.
A case of mistaken identity
Last month, autonomous system 209243, which belongs to UK-based network operator Quickhost.uk, suddenly began announcing its infrastructure was the proper path for other ASNs to access what’s known as a /24 block of IP addresses belonging to AS-16509, one of at least three ASNs operated by Amazon. The hijacked block included 220.127.116.11, an IP address hosting cbridge-prod2.celer.network, a subdomain responsible for serving a critical smart contract user interface for the Celer Bridge cryptocurrency exchange.