# Bonzo Lend loses $9M in Supra oracle exploit > A zeroed BLS signature on Supra’s Hedera verifier let an attacker turn 250 SAUCE into about $9.05M of borrowed USDC and wrapped HBAR from Bonzo Lend on July 11. - **Source:** https://ptycoin.com/en/posts/2026-07-14-bonzo-lend-supra-oracle-exploit/ - **Published:** 2026-07-14 - **Category:** News - **Author:** Mateo - **Tags:** security, defi, self-custody, stablecoins, latam - **Also published in:** [Español](https://ptycoin.com/es/posts/2026-07-14-bonzo-lend-supra-oracle-exploit/) --- **Bonzo Lend**, Hedera’s largest DeFi lending pool, lost about **$9.05 million** on **July 11, 2026** after an attacker posted a forged **SAUCE** price through a third-party **Supra** oracle verifier that accepted a **zeroed BLS signature**. Eight seconds after the bad price hit storage, a few dollars of collateral unlocked millions in **USDC** and **wrapped HBAR**. ## What happened on-chain According to Bonzo Finance Labs’ [preliminary incident report](https://bonzo.finance/blog/bonzo-lend-incident-report-oracle-provider-exploit), **Wallet A** deposited **250 SAUCE** (worth a few dollars at the real market) as collateral at **00:39 UTC**. At **00:51:39 UTC**, the same wallet submitted a price update for the SAUCE/wHBAR pair. The price field was inflated by roughly **twelve orders of magnitude** relative to the true ~0.2 HBAR market level (Bonzo says the field carried the integer 1 followed by thirty zeroes), while real SAUCE markets did not move. Eight seconds later, Wallet A borrowed **6,634,528 USDC**, then **34,518,389 wrapped HBAR**, about **$9.05 million** of principal at Bonzo’s HBAR reference of **$0.06998**. [The Defiant](https://thedefiant.io/news/hacks/bonzo-lend-loses-9m-on-hedera-in-supra-oracle-exploit) and [CryptoSlate](https://cryptoslate.com/how-a-zeroed-oracle-signature-unlocked-9m-from-hedera-defi-lender-bonzo-lend/) independently match those figures against the same report and public Hashscan traces. A second account, **Wallet B**, borrowed about **$1 million** more while the abnormal price stayed live, then contacted the team on Discord as a white-hat responder and said it intends to return the funds. Bonzo excludes that amount from the headline **$9.05 million** figure pending return; combined abnormal borrowing was about **$10.06 million**. Bonzo paused the lend pool at **01:41 UTC** and later paused Bonzo Points. **Vaults, Bridge, and BONZO/XBONZO staking** were not affected, per the report. As of July 13, the pool remained closed with no public reimbursement plan or reopening date. ## Root cause: a verifier that trusted the wrong “yes” This was not a flash loan, a market push on SAUCE, or a bug in Bonzo’s loan-to-value math. Bonzo reads prices from configured oracles (Supra for most ecosystem assets, plus Chainlink elsewhere). Supra’s push feed is supposed to accept only committee-signed updates before writing a new value to on-chain storage. Bonzo’s contracts only read that stored value and apply configured LTV rules. Wallet A’s update carried a **zeroed signature** (the field was **`[0,0]`**) and a zero (identity) committee public key. Supra’s verifier did not reject those identity inputs before calling **Hedera’s pairing precompile** (system contract `0.0.8`). Under the pairing equation, identity inputs produce a true result by design; the precompile answered the math correctly. The verifier then treated that true result as proof of a valid committee signature, which it never was. [CryptoSlate’s write-up](https://cryptoslate.com/how-a-zeroed-oracle-signature-unlocked-9m-from-hedera-defi-lender-bonzo-lend/) puts the same failure in plain language: the network answered the equation it received; the verifier mistook that answer for authorization. Bonzo is explicit that **no valid oracle signature was forged** and that SAUCE’s real market price did not rise. Supra has acknowledged the issue and, according to Bonzo, **deployed a fix** to the affected verifier on Hedera mainnet. The report lists full on-chain references, including the [manipulated price update](https://hashscan.io/mainnet/transaction/0.0.995584-1783731093-686041919) and Wallet A’s account, for independent verification. ## Fallout and where the funds went DefiLlama-tracked value locked on Hedera and in Bonzo itself dropped hard in the hours after the raid: The Defiant cites roughly a **40%** one-day drop in Hedera TVL and about a **77%** drop for Bonzo, with Bonzo’s remaining TVL near **$3 million**. Security researchers tracking the trail said more than **$5 million** of extracted value was bridged toward Ethereum via LayerZero and rotated into ETH within hours, a familiar post-exploit path once liquidity leaves a smaller chain’s venues. The practical status for users is still a hard pause. Liquidity providers cannot withdraw while Bonzo Labs and the Bonzo Finance Foundation decide recovery terms, reimbursement, and conditions for reopening. That gap between “oracle patched” and “pool open” is where most depositors feel the damage: the attack window lasted under an hour, but access to remaining capital does not resume on the same clock. ## Why this pattern matters beyond Hedera Latin American DeFi and stablecoin use keeps growing on large chains and on smaller networks that pitch lower fees and local partnerships. Lending protocols everywhere still share one architectural fact: **collateral value is only as honest as the price feed**. A pool can audit its own contracts and still lose millions if an upstream verifier accepts identity cryptography as a committee vote. That is the same family of risk that showed up in earlier 2026 DeFi incidents PTYcoin covered (governance-weight raids, key theft, and oracle-edge cases), even when the dollar size differs. The self-custody lesson is narrower than “never use DeFi.” It is: treat any venue where your claim depends on someone else’s oracle, multisig, or admin key as **counterparty risk with a blockchain wrapper**. Funds in a wallet you control are not the same product as shares in a paused pool waiting on a foundation recovery plan. For readers who supply liquidity or borrow on-chain, the checklist this incident refreshes is concrete: which oracle provider signs each collateral asset, whether the protocol has **deviation caps** or secondary feeds, whether a pause is permissionless or foundation-controlled, and how much of your net worth sits in any single pool. None of that required a novel attack; it required one missing zero-check. ## Takeaway Bonzo Lend was drained of about **$9.05 million** on July 11 because Supra’s Hedera verifier accepted a zero-signature SAUCE price and Bonzo’s contracts correctly followed a wrong number. The lend market is still paused; a white-hat wallet may return about **$1 million** more; Supra has patched the verifier. If you hold funds in any lending protocol, size the position as if the price feed can fail in ways the pool code never imagined, and keep long-term savings in self-custody you can move without a status page. Not financial advice. --- ## Keep reading - [Self-custody without a single point of failure](https://ptycoin.com/en/posts/2026-08-10-self-custody-without-single-point-of-failure/index.md): A hardware wallet can generate a key badly. Build a self-custody setup that survives a vendor bug: verified backups, your own entropy, passphrases, and multi-vendor multisig. - [How to check and revoke token approvals](https://ptycoin.com/en/posts/2026-08-04-token-approvals-check-and-revoke/index.md): A token approval lets a dapp spend your USDT or USDC later without asking again. Learn how unlimited allowances work, how to list them, and how to revoke the ones you no longer need. - [How to plan gas so your stablecoins stay spendable](https://ptycoin.com/en/posts/2026-07-28-gas-planning-native-fees-stablecoins/index.md): USDT can land in a wallet and still be unspendable. You need the chain's own coin for fees. This guide shows how to keep TRX, ETH, SOL, and similar gas ready before you need it. --- Source: PTYcoin — https://ptycoin.com/en/posts/2026-07-14-bonzo-lend-supra-oracle-exploit/. Free to read and cite with attribution to ptycoin.com. AI-usage terms: https://ptycoin.com/en/ai-usage/