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Monthly Security Review: June 2024

July 1, 2024
4 min read

Security at a Glance 👀

DeFi Sector

  • UwU Lend Hacks

On June 10 and 13, UwU Lend suffered attacks resulting in losses exceeding $23M.

The root cause of the first attack was Vulnerable Price Dependency. The lending pool fetched prices from 11 sources, including 5 current (AMM) prices from Curve, 5 Curve oracle (EMA) prices, and one Uniswap (TWAP) price, ultimately taking the median. Since current prices could be manipulated within a single transaction, the attacker used a flash loan to drastically alter the 5 current prices, causing the fetched price to be the minimum or maximum of the oracle prices. This resulted in a loss of approximately $20M.

On June 13, the UwU Lend team restarted the protocol and got attacked again. The attacker added uSUSDe and WETH as collateral and then borrowed WETH based on the LTV. The uSUSDe did not participate in the LTV but did in the health factor calculation during liquidity withdrawal, allowing the attacker to withdraw more WETH and profit.

Notably, white hat makemake_kbo tweeted that he had reported the vulnerability a year ago and contacted the project team without a response, eventually issuing a warning on Twitter.

  • Velocore Hack

Root Cause: A lack of check on effectiveFee1e9 led to an underflow in the velocore__execute function.

After the attack, Linea halted block production for 1 hour. For L2 projects, having an emergency response mechanism is more effective than pausing the entire chain. 👉 Learn about the world's first crypto hack monitoring and blocking platform here.

  • Holograph Hack

Holograph announced that a former contractor exploited the protocol to mint additional HLG.

Many past attacks have shown that projects often compromise private key management for convenience. This exposes them to severe risks of internal and external attacks gaining admin permissions or private keys. Using Phalcon Security for external monitoring allows one-click operational monitoring, enabling early detection and loss minimization.

Other

  • DMM Exchange Hack

In early June, DMM Exchange disclosed a security incident where 4,502.9 BTC (over $300M) were stolen on May 31 (UTC).

Without more details from DMM, the cause remains unknown. However, the hacker's address and DMM's normal address shared the same first five and last two characters, and the stolen BTC was from a multisig address. Speculation suggests an off-chain attack replaced the transfer address, deceiving personnel into signing the transaction. Use MetaSleuth to track the funds here.

  • Kraken

On June 19, Kraken's Chief Security Officer, Nick Percoco, disclosed on X that they had received a report of an "extremely critical" vulnerability from a security company through their bug bounty program. The report claimed to have found a vulnerability that could artificially increase account balances. However, after Kraken fixed the vulnerability, they discovered some suspicious behavior during negotiations with the security company, involving $3 million. Nick Percoco's Post: View Post

CertiK later claimed responsibility for the matter on X, disclosed more information, and explained their actions. They emphasized that they had conducted multi-day tests on Kraken and had already returned the funds. This incident sparked intense discussion within the community.CertiK's Post: View Post Check out the root cause here and the sample transaction here.

  • CoinStats

CoinStats suffered a $2 million loss in an attack. Their CEO stated that the breach was due to a social engineering attack on an employee, which compromised their AWS infrastructure. Click here to learn more

Blog Articles

BlockSec has curated the "Solana Simplified" series, which includes articles on Solana's basic concepts, tutorials on writing Solana smart contracts and guides for analyzing Solana transactions. The goal is to help readers understand the Solana ecosystem and master essential skills for developing projects and conducting transactions on Solana.

01: Master Solana Core Concepts in One Read

02: Writing Your First Solana Smart Contract from Scratch

03: Understand Solana Transactions in 5 Minutes

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From June 20 to June 22, BlockSec proudly presented at the 2024 Solana Summit APAC in KL. Looking forward to meeting you all at more global events in the future!

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Bitget's $387.5M Off-Chain Breach: Beyond Keys and Contracts
Security Insights

Bitget's $387.5M Off-Chain Breach: Beyond Keys and Contracts

On September 24, 2026, attackers exploited a vulnerability in a third-party security product, obtained internal credentials, and forged withdrawal commands. The resulting transfers moved approximately $387.5M from some of Bitget's operational wallets across Ethereum, other EVM networks, XRP Ledger, Zcash, and TRON; private keys and cold wallets remained intact. This deep dive summarizes the disclosed incident path and fund flow, examines rapid conversion into native assets and the ecosystem recovery response, proposes a systematic defense-in-depth framework for institutions, and explains how authorized blockchain penetration testing can validate cross-layer assumptions.

~$11.3M Lost: Multicall Router, Nostra | BlockSec Weekly
Security Insights

~$11.3M Lost: Multicall Router, Nostra | BlockSec Weekly

This report, covering 2026/09/14 - 2026/09/20, examines two security incidents with approximately $11.3M in combined losses, on Ethereum and Starknet. In the larger one, a multicall router accepted its own address as a dispatch target, so the nested call reached the Gateway module of a Safe wallet carrying the router's own already-authorized identity instead of the external caller's, and roughly 2,900 `aEthrsETH` was routed out of that wallet into an attacker-created Uniswap v4 pool. On Starknet, Nostra's oracle integration required a minimum of only one aggregated source, so when only two of the three configured price sources reached the aggregation, a manipulated thin-pool quote averaged with a normal quote to value `NSTR` at roughly $49.52, supporting approximately $3.5M of borrowing against overvalued collateral.

~$320M Lost: Liquid Network, Symbiosis Exploits | BlockSec
Security Insights

~$320M Lost: Liquid Network, Symbiosis Exploits | BlockSec

This report, covering 2026/09/07 - 2026/09/13, examines two security incidents that caused approximately $320M in losses, including the Liquid Network exploit of 2026/09/06 that the previous report did not cover. The larger was that Liquid Network exploit, where the rangeproof validation cache in Elements derived its key by hashing four fields — two of them variable in length — concatenated with nothing marking the boundaries between them, so a verdict recorded for one output was returned for another whose proof was never examined, letting the attacker create 4,000 unbacked L-BTC and peg out nearly all of them as bitcoin. On the Bitcoin route of the Symbiosis cross-chain bridge, spanning BNB Smart Chain, Ethereum and Rootstock, off-chain code that reads Bitcoin deposits took the depositor's identity from a field the depositor controls and then subtracted its fee from the deposit without checking whether the fee itself was negative, letting a 330-satoshi deposit mint `46,116,860,184.27388234 syBTC`; the pools it had to be sold through held only 11.26 syBTC, so the loss to liquidity providers and users came to an estimated 9.97 BTC (~$770K).