Bancor

Hackers steal $23.5M in cryptocurrency from 'decentralized' crypto exchange Bancor.

Attackers used a compromised wallet to steal $12.5 million of ether, $1 million of Pundi X, and $10 million of Bancor Network Tokens (BNT).

Bancor was able to mitigate the damages down to $13.5 million

No user wallets were compromised, but a wallet used to upgrade some smart contracts was compromised.

Source: https://www.csoonline.com/article/3289384/hackers-steal-235m-in-cryptocurrency-from-decentralized-crypto-exchange-bancor.html#:~:text=How%20the%20Bancor%20hack%20happened,of%20Bancor%20Network%20Tokens%20(BNT)

"id": "BAN12491122",
"linkid": "bancor-foundation",
"type": "Breach",
"date": "07/2018",
"severity": "100",
"impact": "5",
"explanation": "Attack threatening the organization’s existence"