Organizer: Stefanie Kettler
Over the past decade, cryptocurrencies have become phenomenally successful with a total market capitalization well above USD 100 billion, and a trading volume of more than USD 5 billion per day alone for Bitcoin. In cryptocurrencies funds are assigned to addresses that are stored on the blockchain -- the underlying backbone of most cryptocurrencies. At a technical level, an address in a cryptocurrency is represented by a public key of a digital signature scheme. To spend funds to a different address, the owner of the funds creates a transaction that transfers the money to this new address. These transactions must be signed with the corresponding secret key of the owner as otherwise they are not accepted and processed by the miners.
Because the owner of secret keys is in full possession of the funds, cryptocurrencies make secret keys a highly attractive target for attacks. Unsurprisingly, there are countless examples of spectacular hacks where the attacker was able to steal millions of dollars by breaking into a system and extracting the secret key. This is where cryptocurrency wallets come into play -- to ensure secure key generation, storage and management and of course interaction of these keys with the blockchain. Despite immense importance of wallets, formal modeling of such schemes have not been well studied yet in the literature. One of the current projects in S7 is working on the problem discussed above -- by capturing the security properties a wallet should satisfy, and finding out what notion of (provable) security it can achieve. This talk will give an overview of the same.
After completing her Masters in Hardware Security from Department of Computer Science and Engineering, Indian Institute of Technology Kharagpur, India in 2017, Poulami worked as an intern in the Max Planck Institute for Software Systems in Saarbruecken. Since March 2018, Poulami started her PhD in Applied Cryptography in TU Darmstadt. Her research area of interest involves -- design of provably secure protocols for blockchain technology.