ChainBleedv0.1 · open intel
← back to feed·2021-09-27 · 4y ago
Incident · SLOWMIST

Bitfinex

Handle inventory defects with fixed precision and extended value range
Estimated loss
VERDICT —UNRATED
Verdict pending. Auto-ingested incidents are reviewed before a public verdict is rendered.
▰ METHOD
Undisclosed
Root cause

Root-cause analysis not yet published. The incident description below contains all currently available signal — review the attack transaction directly for definitive forensics.

Forensic narrative

The non-custodial exchange DeversiFi released a post-mortem analysis report for the previous gas transaction that included 7676.62 ETH, saying that the potential problems in the EthereumJS library are combined with the gas fee changes related to the EIP-1559 upgrade in some cases, and the Ledger hardware wallet may exist The display problem of, may lead to extremely high transaction fees. When this happens, only wallets with very large funds will be affected, and other users will display transaction failures during transactions. In addition, after Bitfinex negotiated with the miners, the miners had returned 7,626 ETH, and the remaining 50 ETH was provided to the miners as a refund fee. It was previously reported that a major wallet on the Bitfinex exchange made a $100,000 USDT transfer with a total of 7676.62 ETH (approximately US$23.54 million) in Gas fees. The final recipient was a non-custodial spin-off from Bitfinex in 2019. Exchange DeversiFi. Attack method (per SlowMist): Handle inventory defects with fixed precision and extended value range. Reported loss: 50.62 ETH.

Primary source
https://blog.deversifi.com/23-7-million-dollar-ethereum-transaction-fee-post-mortem/
Sourced from
slowmist
Technical record
chain
protocol
Bitfinex
bug_class
unknown
date_occurred
2021-09-27
loss_usd
source_id
sm:bitfinex::2021-09-27
Related — same bug class
2026-05-16
25d ago
ETH
Adshares
Bridge-Minter Fake-Mint Exploit (wADS)
bridge
$628.0K
AMBIGUOUS
2026-05-15
26d ago
MULTI
THORChain
Cross-Chain Router Exploit (multi-chain drain)
bridge
$10.70M
AMBIGUOUS
2026-05-13
27d ago
BSC
Mail Token
BSC token contract exploit (vector undisclosed)
accounting
$54.6K
UNRATED
2026-05-13
27d ago
ARB
ShapeShift FOX Colony (Colony Network)
executeMetaTransaction → resolver-repoint via setTarget → delegatecall drain
access-control
$132.7K
AUDIT-CATCHABLE
2026-05-13
28d ago
ETH
Transit Finance
Contract Vulnerability
logic
$1.88M
UNRATED
2026-05-13
28d ago
ETH
TAC Cross-Chain Layer (TON Side)
Contract Vulnerability
logic
$2.80M
UNRATED
ChainBleed — live web3 threat intelligence