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3/16 Hack - Technical Post-Mortem Today Remilia’s hot wallets and its multisignature treasury (https://etherscan.io/address/0xcf3e932f72e5f15411d125ad80579a3ef205b9b4…) were drained. The attack took place in two waves. The first wave begins at 6:36pm UTC. The attacker 0x778Be423ef77A20A4493f846BdbcDDfc30252cE9 (https://etherscan.io/address/0x778Be423ef77A20A4493f846BdbcDDfc30252cE9…) begins (https://etherscan.io/tx/0x275bc80a66c8e84756d7b36e3fd5f199fe9e586848687fd62d37f5ecb321bc50…) transferring assets away from Remilia. Remilia becomes aware of the attack at approximately 7:30pm UTC. At this point the Remilia multisignature treasury requires 3/4 signers to execute a transaction. The attacker has obtained the private keys for - charlemagnefang.eth (https://etherscan.io/address/0x3fad44f892b986263ac69db971db8da172185387…), - remiliadao.eth (https://etherscan.io/address/0x4Cc17f677c1271bAba0d10df83438821B5F8EAf4…), - the first multisignature participant remiliacollective.eth (https://etherscan.io/address/0xB520F068a908A1782a543aAcC3847ADB77A04778…), - the second multisignature participant 0x70b8fee0975b4f6249e44523df2dde3866251b96 (https://etherscan.io/address/0x70b8fee0975b4f6249e44523df2dde3866251b96…), - the third multisignature participant 0xa77Eb0d4e2736c1FF7387CAdD3D0E6a67261a26a (https://etherscan.io/address/0xa77eb0d4e2736c1ff7387cadd3d0e6a67261a26a…), - the Fumo ERC-20 token liquidiiy manager 0xA1A58311407Ab018141532e8Cf0a9CCCD1Bc9052 (https://etherscan.io/address/0xa1a58311407ab018141532e8cf0a9cccd1bc9052…). The attacker transfers - 195.1 Ether obtained from pulling liquidity from the Fumo ERC-20 token (https://etherscan.io/tx/0x394a9b1e0a397b327431eed3690301adf1483d03d0b4afd71035b9bedec44673…). - 61 Ether from the Remilia treasury (https://etherscan.io/tx/0x21a912ae69d79e25458d7ca2ceb5cd35f85b245b55c5f510422e0807814cc5e4…). - 110 Miladys from the Remilia treasury (https://etherscan.io/tx/0x4af80b61f19746335e80527a4a08e409e5e6d92dac371ff9448810189311078f…). - $58k USDC from a hot wallet (https://etherscan.io/tx/0x542e7cfd3eb9776e24fc94233186571398f08f793dac8a4b194d16a6f8070caf…), - 144 Milady from NFTx liquidity (https://etherscan.io/tx/0x879925e9321c820fc66edcb3fe4c5602e6d8c71efd50526d7cbfee77cc39dddf…), - 105 Remilio from NFTx liquidity (https://etherscan.io/tx/0x53f1dafebf9c69877a4a2d851b88b872bf38af9d9a06c0c7411a272db7a76a9b…), - 6 Ether and 148 Kagami from NFTx liquidity (https://etherscan.io/tx/0x875f9a126bb12085e96b7bab666e4f9a21366d6f4376fab7ce52397ada507867…). At this point Remilia considers the feasibility of imploring NFTx to use their upgradeable contracts to rescue the NFTx tokens. Given that the contract is upgradeable (https://etherscan.io/address/0x227c7df69d3ed1ae7574a1a7685fded90292eb48#readProxyContract…), it would be possible for NFTx to have upgraded the implementation to freeze and return the attacker’s tokens, for instance. However, this rescue option remains purely an academic exercise to consider. There simply is not the time to have coordinated the upgrade in the middle of the attack. At 8:46pm UTC, Remilia attempts to halt the attack on the Remilia multisig by increasing the signature threshold to 4/4 (https://etherscan.io/tx/0xcfadb5d2a85bf2c00d625782bfd56d18bc86641ec44f57cf97a8cf37dac7310a…). At this time it is not clear if the attacker has the private key for the fourth multisignature participant, 0x1149124FFED5Ce739bcA9dbD52348723332b4254 (https://etherscan.io/address/0x1149124FFED5Ce739bcA9dbD52348723332b4254…). After the threshold on the treasury is increased, Remilia attempts to rotate the treasury to all new multisignature participants. Out of caution and under the assumption of a browser exploit, Remilia shuts down the machines that held the hot wallets and moves to fresh hardware. After reboot, Remilia is unable to log into the Bitwarden account where the private keys and wallet passwords were stored. The worst has happened. At this point it is clear the attacker had compromised the Bitwarden account, and now has direct access to Remilia’s private keys while Remilia no longer has been locked out of its own accounts. Unfortunately the treasury was not secure as the private key for 0x1149124FFED5Ce739bcA9dbD52348723332b4254 was also stored in the same Bitwarden account with minor obfuscation. At 11:56pm UTC, the attacker adds himself to the multisignature treasury (https://etherscan.io/tx/0x4e1fb20d916bd32d95b43cfe2bc1ac244391ff3c685671a97666e3e93ba2777a…), proceeds to remove the other multisignature participants, and begins transferring more assets. At this point it is game over and the multisig assets are fully-compromised. The attacker transfers - 17.4 WETH from the Remilia treasury (https://etherscan.io/tx/0x58c4db88f0ec455dd9423bada7d5a09699a365fee42c039927018e553eba0413…), - 3 Ether to a new wallet 0x8AC9dbd9C719806F0a48D7bC60D005AD0B18d35c (https://etherscan.io/tx/0x3e6ce0cc52c6a7fbbbf2153a9006cd3224988a783fe61a962e299c7dce001dcf…). - 22 Miladys, 12 Bitch tees, 106 Remilios to 0x8AC9dbd9C719806F0a48D7bC60D005AD0B18d35c (https://etherscan.io/tx/0x681f09559910a8dfb0a6a02199d63d883c58b2d80a1cc7d4b95b7faad843a075…). - 214 Remilios to 0x8AC9dbd9C719806F0a48D7bC60D005AD0B18d35c (https://etherscan.io/tx/0x3c19c315bd9750e7afaad08fa4d7dcbcf770fc1f491b972996ead00dc1065a9f…). - 211 Ether from the Blur pool (https://etherscan.io/tx/0x94e8e2c3931250646ef017816f916b51bd6a6f03eb8aa932e3c635f217946455…). As of writing, the attacker seems to have concluded selling every transferred NFT. Most worthwhile on-chain assets in the Remilia treasury and hot wallets have been transferred away, and as of now all the Milady and Remilio NFTs have sold been sold into bids on the market. Remilia’s primary operating treasury remains secure as it is held off-chain. Questions: How did the hack happen? - Remilia doesn’t know for certain. The assumption is malware on a device that granted the attacker access to the critical Bitwarden account, or the account’s master password was brute-force cracked directly. Why wasn’t the Fumo ERC-20 liquidity locked? - Fumo launched as a direct Unisocks copy as a fun model for the gamified distribution of a large doll during a limited redemption period. The intention wasn’t to make a memecoin, but after launch, it was decided to allow the LP to continue beyond the closure of the redemption window to allow continued trading on the conversion to the NFT. The Fumo liquidity tokens should have been programmed to be locked, burnt, or otherwise secured after the decision was made to extend the LP indefinitely. Over-reliance on the security of the single EOA was not sufficient. Why were all multisignature keys stored in the same Bitwarden account? Why was there no physical backup of keys? Why was there no timelock on the treasury? - This management setup was clearly insecure. A sophisticated framework for on-chain security had been recommended shortly after the events of 9/11 but implementation was unfortunately delayed in pursuit of other priorities and left in an insecure state. Remilia is immediately moving to a correct multisignature implementation. Signers will be multiple discrete personnel using unique hardware devices instead of cloud-stored private keys prone to lockout and attacker access. Assets will be split across in multiple vaults arranged in a circle (vault one drains to vault two, vault two drains to vault three, vault three drains to vault one) with emergency fallback to different evacuation addresses. Assets will need to pass through a timelock before being transferred anywhere. Allowances will be implemented on the vaults at the contract level. In short, Remilia will be using the model seen in the battletested AssetVault system deployed here (https://etherscan.io/address/0xa74eBcBBBbA1122d57176eF5AD5b6466D60D2B33#code…). Remilia will ensure this framework is in place and transparently outlined as an immediate next steps before any new on-chain launches take place. How does this affect Remilia NFTs? - The contract ownership and control of the metadata for all Remilia’s NFTs had previously been migrated to the secure hardware wallet (0x54F8E4E9842c93EF0E8F5A83374db0C521D728cB), so luckily they are perfectly safe. The only major effect is the sudden supply shock of assets being dumped on the open market, which has now concluded. On the optimistic side, one can say the NFT treasury has been decentralized. Unfortunately, ownership of the $FUMO LP is compromised and not salvageable. Will Remilia survive? - Of course. Remilia’s primary operating treasury is held securely off-chain, leaving the runway already budgeted to pursue its planned projects unaffected, so there is no reason to not see things progress as normal. This event hurt the Fumo project and its $FUMO holders, and the price of our primary NFTs, but otherwise represented the theft of a long-term treasury of own assets which we did not have any intention to sell or liquidate any time soon. Our actual operating budget is unaffected beyond the ETH that was being held for on-chain expenses. There is no drainer, we’re sorry but we love you. Tweeted at 19h

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