After ralying over 80% in the last month, Bitcoin prices are tumbling (down 25% from record highs to 2-week lows) as cryptocurrencies face uncertainty on three fronts.

As iBankCoin reports, investors are spooked over recent cyberattacks, uncertainty surrounding a Bitcoin platform upgrade, and proposed legislation which adds cryptocurencies a list of reportable assets under existing anti-money laundering laws.

Cyber attack

As CNBC reports, major bitcoin exchanges were hit with multiple cyberattacks this week. Bitfinex, the largest U.S. dollar based bitcoin exchange, announced it was under 'distributed denial-of-service' attacks (DDOS) which slowed the service down.  The attacks come at a time when consumer interest in bitcoins have also led to heavier than normal traffic on the exchanges, compounding the attacks.