Serious security concerns with blockchain elections

No democracy without trustworthy elections? MIT researchers have strong doubts as to whether the blockchain has a future-proof solution when it comes to voting.

The allegations of election fraud brought forward by the outgoing US President Donald Trump are putting the democratic process under pressure. This development has sparked thought about whether the election procedure could not be better protected from allegations and actual attempts at manipulation. Famous representatives from the crypto space formulated a solution that could be expected : Blockchain-based elections. But of all things, the Massachusetts Institute of Technology (MIT) recently put a damper on these plans.

Scientists from the renowned research institute presented the results of a study on November 6thpublished on the security aspects of Crypto Method and other online voting systems. The authors arrive at a clear result:

Internet- and blockchain-based voting would significantly increase the risk of undetected, nationwide elections being lost.

Online voting has too many points of attack

The researchers say they are positive about efforts to make elections more efficient and to remove obstacles that (especially in the US) prevent certain groups of voters from voting. Nevertheless, they have reservations that speak against voting via the Internet and blockchain.

They remind you that the security concerns in elections are of a different dimension than in online shopping and Co. After all, there is no insurance against a “failure of democracy.” As long as it cannot be sufficiently ensured that all votes are counted correctly, they ran all efforts to improve the electoral procedure come to nothing.

A key argument here is that Internet-based attacks are much easier to carry out on a large scale. They may be hard to spot. The cost of such an attack is also much lower. MIT researchers also point out that the security of devices that are part of the voting system depends on too many factors:

Errors in the voting system can be caused by the provider of the voting software, the hardware manufacturer, the manufacturer or a third party who maintains or supplies the code for these organizations. The voter who uses a telephone to cast their votes depends not only on the telephone provider, but also on the hardware companies that provide drivers for the device […]

What does blockchains offer?

As far as blockchain elections are concerned, the authors note the same fundamental reservations as with other online systems. Consensus mechanisms and encryption are not enough for them to allay their concerns.

First, they are discussing a model in which votes are cast via tokens on a public blockchain. Each voter sends a public key to a blockchain-based electoral roll. He then receives a coin with which he can vote for his candidate. The MIT researchers see the problem here that the ballot papers are not secret, since all votes are cast publicly. This opens up mechanisms of influence such as the purchase of votes (“I can prove that I voted for candidate XY”) or an agreement between miners. In addition, public blockchains are vulnerable to DDOS attacks.

Permissioned blockchains should not be able to solve the problems either. On these centrally managed blockchains, depending on the setting, the problem could arise that the users cannot verify whether their vote was actually counted.

Finally, they discuss an elective solution based on zero knowledge proofs. Information can be confirmed here without sharing it. Thus, secret elections seem possible, in which the voting can still be verified. However, here too there is no satisfactory mechanism against influencing and buying votes for the authors.

Finally, the authors also rate key management as fundamentally problematic. In particular, voters who are not particularly tech-savvy could have problems here.