727 FinanceBinance hot wallet hacked for 6.28 billion USD; on-chain tracking reveals how the attacker used EIP-7702 authorization to take over the wallet and moved funds before Tether and other issuers could freeze them, providing a full reconstruction of this largest security incident.
Author: Dickson (@DicksonWuML)
Compiled by: Shenchao TechFlow
Shenchao Introduction: The theft from Binance's hot wallets is the biggest event in the crypto market today. CertiK engineer and SEAL member Dickson traced the on-chain records transaction by transaction, reconstructing the full process of the attacker preparing funds by withdrawing from Tornado Cash, using EIP-7702 authorization to take over Binance's Ethereum hot wallets, and racing against Tether, Circle, and other issuers to freeze funds. The amounts and times in this article are on-chain statistics as of the author's posting time (around 8 AM Beijing time on October 30), with times in UTC (+8 hours equals Beijing time), and have not yet been officially confirmed by Binance.
Binance's hot wallets lost approximately $6.28 billion across 8 chains today. Of that, $6.07 billion was transferred out within the first 55 minutes, after which the attacker repeatedly swept one of the Ethereum wallets for more than two hours.
Since then, Tether, Circle, Ripple, Paxos, World Liberty, and Binance have frozen approximately $2.80 billion. About $3.27 billion can still be moved freely, mainly BTC and ETH.
I traced the entire incident on-chain, including how the attacker moved funds before the freezes 🧵
Breakdown of the $6.28 billion (priced at UTC 20:24):
• Ethereum $3.74 billion
• Bitcoin 18,270.2 BTC, $1.47 billion
• Tron $612.7 million USDT + 46.4 million TRX, $627.5 million
• XRP 233.5 million XRP, $296.5 million
• Solana 970,522 SOL, $96.1 million
• Arbitrum 8,426 ETH + 74.6 million ARB, $31.8 million
• Avalanche 1.81 million AVAX + 8.41 million USDt, $24.3 million
• Optimism 44.2 million OP, $4.8 million
The $3.74 billion on Ethereum flowed out in five batches:
• 20:24:23, a single sweep() on Binance 14: 167,464.25 ETH, $1.615 billion USDT, and 61 other tokens, totaling $2.53 billion
• 20:41 and 20:59, 780 million + 43 million USDC transferred out from a Binance smart wallet that trusted Binance 14, totaling $822.6 million
• 20:24:47, Binance 16 signed 9 transfers sent directly to the attacker: 28,005.6 ETH, 55.7 million USDT, 25.9 million RLUSD, 84.5 WBTC, 820,000 UNI, 1,199 XAUt, 18.8 million ENA, 304,600 LINK, 583.6 billion PEPE, totaling $174.2 million
• 21:04 and 21:44, two additional sweeps of Binance 14: 2,070 ETH and 204.3 million USDT, totaling $209.6 million
• 22:39, a final sweep to a new wallet: 128.5 ETH and 122 small-cap tokens, about $500,000
By asset: $1.87 billion USDT, $823 million USDC, $457 million ETH (197,668 ETH), $88.5 million RLUSD, $76.8 million wBETH, $50.5 million XAUt, $49.6 million UNI, $44.7 million ENA, $40.1 million PEPE, $29.6 million LINK, $27.8 million USD1, plus about 50 smaller tokens.
Preparation began the day before. On October 28 at UTC 07:39, the attacker's main wallet 0x7c8601d4645b93cea45f71e118a729332e6b5ca0 first withdrew 0.1 ETH from Tornado Cash, then withdrew twice more. A second wallet then withdrew 1 ETH from Tornado and transferred it to the main wallet on October 29 at 18:20.
On October 29 at 02:28, they deployed a sweeper contract. From 13:51 to 16:47, they rehearsed on their own wallets: using EIP-7702 delegation, sweeping test USDT and USDC, then withdrawing. At 15:59, they deployed a v2 version with a generic call function, and it was this function that later moved the $823 million USDC.
At UTC 20:04:52, the first step failed. Binance's XRP wallet sent 42,750,000.1 RLUSD to the attacker, but the attacker's XRP account did not yet exist, so the transfer was returned.
Eight seconds later, 185,017,485.5 XRP was transferred successfully, thereby creating the account. By 20:09, four other Binance XRP wallets had also been emptied.
A chain reaction followed:
20:10 Solana, 965,455.1 SOL moved in a single transaction
20:18 Optimism, 44.2 million OP
20:20 Bitcoin, 18,270.2 BTC moved in 11 transactions and split into 1,000 BTC chunks within the same block
20:20 to 20:22 Tron, $612.7 million USDT + 46.4 million TRX
20:30 to 20:35 Arbitrum and Avalanche
Ethereum revealed the attack method. At 20:20:59, the attacker sent a transaction carrying 50 EIP-7702 authorizations, all signed by Binance 14's private key, corresponding to nonces 18,914,775 through 18,914,824.
Binance 14 itself had just used 18,914,775 at 20:17:47, indicating that these authorizations were signed only minutes before use.
The authorization with nonce 18,914,809 matched. Binance 14's own transaction in the same block used 18,914,808, and from that moment on, Binance 14 was running the attacker's code.
At 20:24:23, a single sweep() moved 167,464 ETH and $1.615 billion USDT out of it. Twenty-four seconds later, Binance 16 signed 9 transfers sent directly to the attacker. At 20:41 and 20:59, the attacker used Binance 14 to transfer $823 million USDC out of a Binance smart wallet that trusted it.
Next came the race against the freezes. The attacker quickly split the USDT:
• At 20:30, $500 million USDT was transferred to 0x9749…c762. By 20:59, $325 million of it had been swapped into ETH through RFQ market makers, and the remaining $175 million was transferred onward
• At 20:33, $200 million USDT was transferred to 0x0ddf…697e. About $10 million was sold on DEXs, and $190 million was transferred to 0x8d53…639a, which deposited $60 million into Aave and borrowed ETH against it
Tether's first batch of blacklistings took effect at 21:01:35: 0x5227, which still held $971 million USDT; and 0x9749, which had already been emptied. Circle froze the $823 million USDC at 21:04:59.
Some funds escaped in the final seconds:
• At 21:01:59, 0x8d53 transferred $130 million USDT to 0x77ed…c3eb. Forty-eight seconds later, at 21:02:47, Tether froze 0x8d53• 21:04 to 21:06, 0x77ed sold about 50 million USDT on a DEX and transferred 80 million to 0x7aa4…bfd1
• 21:08 to 21:11, 0x7aa4 sold another approximately 50 million and moved the final 30 million out. By the time Tether froze 0x7aa4 at 21:12:35, it had already been emptied
• 21:16:11, 0xccbe…a263 transferred out the 30 million. 36 seconds later Tether froze 0xccbe, and at 21:18:59 it intercepted the 30 million at 0xb171…c8c3
• The 175 million transferred out by 0x9749 remained at 0xaa24…54a0 until Tether froze it at 21:14:59
In total, of the 1.875 billion USDT on Ethereum, about 435 million was sold before the blacklist caught up. 1.38 billion has been frozen, and 60 million is trapped as Aave collateral.
Actions by other issuers, in chronological order:
• 20:57:47 World Liberty blacklisted 48.5 million WLFI in 0x5227
• 21:07:55 Tether froze 8.41 million USDt on Avalanche. The attacker attempted to move it at 21:40:47, and the transaction reverted
• 21:09 to 21:21 Tether froze 378.7 million USDT in three wallets on Tron. Previously, 234 million had already been swapped into TRX via SunSwap
• 21:11:23 Tether froze 12,574 XAUt (about 50 million USD)
• 22:00:59 Ripple froze RLUSD. The attacker had already moved it to 0xe702…958d at 21:33 and sold 48 million into ETH, with the last sell order and the freeze landing in the same block. 40.5 million was intercepted
• 22:10:35 World Liberty froze 27.8 million USD1
• 22:30:47 Paxos froze 1,907 PAXG
• 22:48:35 Binance blacklisted 29,934 wBETH (about 75 million USD); the attacker had already moved it to 0x7f9d…15e3 at 21:52
First Digital's 3.45 million FDUSD is still transferable.
Binance 14 remained delegated to the attacker's contract, which turned into a tug-of-war:
• At 21:04 and 21:44, the attacker swept again: first 1,700 ETH, then 370 ETH and 200.4 million USDT. This USDT landed in 0x5227, which had already been frozen by Tether
• At 22:06:23, Tether blacklisted Binance 14 itself. Binance's own USDT transfers from that address failed at 22:15 and 23:01
• At 22:39, the attacker swept again, this time to a new wallet: 128.5 ETH and 122 small-cap tokens
• From 22:55 to 23:07, Binance itself emptied Binance 14: 46 token transfers to Binance 8, about one every 12 seconds
• From 23:36 to 23:38, the attacker called sweep() four more times, and all four came up empty
Outside Ethereum:
• Arbitrum, 21:35 to 21:38: all 8,426 ETH and 74.6 million ARB were moved to a new 7702 wallet 0x3e2b…32d5, which authorized ARB for trading at 21:41. As of 23:50 it was still there
• Avalanche, 21:45:34: 1,813,999 AVAX was moved to 0x8035…c397. Then 200,005 AVAX was transferred out from 0xc39e…9824, and at 23:27:35 the same address received 1,563,812.78 USDC on Ethereum via Circle's CCTP cross-chain bridge. Four minutes later, at 23:31:59, Circle blacklisted it
• Funds on Bitcoin, XRP, Solana, and Optimism have not yet moved. BTC is spread across 19 wallets, 17 of which each hold exactly 1,000 BTC
Status as of about 23:50 UTC:
Frozen, about 2.80 billion USD
• 1.38 billion USDT on Ethereum, 378.7 million on Tron, 8.41 million on Avalanche (Tether)
• 824.6 million USDC (Circle)
• 40.5 million RLUSD (Ripple), 27.8 million USD1 (World Liberty), 12,574 XAUt (Tether), 29,934 wBETH (Binance), 1,907 PAXG (Paxos), 48.5 million WLFI
Not frozen, about 3.27 billion USD
• 18,270 BTC, 1.42 billion USD
• 458,770 ETH spread across 9 wallets, 1.03 billion USD
• 233.5 million XRP, 289 million USD
• 684.6 million TRX, 243 million USD
• About 136 million USD in other tokens on Ethereum
• 970,500 SOL, 93 million USD, plus ARB, AVAX, and OP, about 48 million USD
Another 60 million USDT is trapped as Aave collateral.
Note: The transfers on BTC, XRP, and Tron were linked through timing and transaction fingerprints: the same time window, brand-new receiving addresses, and fees and transaction formats different from Binance's own withdrawals. The stolen amount is calculated at UTC 20:24 prices; current holdings are calculated at prices around UTC 23:50.
The on-chain evidence for every transaction and freeze is attached in the post below. If you notice anything I missed, please let me know!