Ethereum’s Pectra upgrade shipped a genuine convenience feature, and the phishing industry integrated it faster than most users learned its name.

EIP-7702 lets a regular account — an EOA — attach smart contract code to itself. Signed once, the delegation gives the account superpowers it never had: batch a dozen actions into one transaction, let someone else sponsor your gas, recover a lost key through social recovery. Wallets and account abstraction projects built on it immediately.

So did drainer kits. Within weeks of Pectra going live in May 2025, Scam Sniffer documented the first case of the new surface being weaponized: on May 24, 2025, a MetaMask user lost approximately $146,600 after signing a malicious 7702 batched transaction. This guide explains the mechanism, why it is qualitatively scarier than approval phishing, and the discipline that neutralizes it. It is part of our Airdrop Safety series because claim pages are the primary delivery vector.

What a 7702 delegation actually grants

Understand the mechanism in one paragraph: an approval grants a contract limited rights over specific assets — it can transferFrom tokens up to an allowance. A 7702 authorization goes further: it makes designated contract code execute as your account. Your address, your balances, your NFTs, your signing power — routed through logic the delegate contains. Where an approval-style drainer must work asset by asset through allowances, a malicious delegate can act with the account’s full authority in one batched transaction.

That is why security teams treated the May 2025 incident as a category change, not another variant. The batched transaction executed under the victim’s account can move holdings that approval-phishing victims would have considered safe — assets sitting outside any allowance.

To be precise about scope: the delegation binds while active and the malicious batch typically executes immediately (attackers do not wait), and the victim’s signature is the only authorization step. No seed phrase, no later confirmation. One click, full account.

Why airdrop pages are the delivery vector

The feature is opt-in — the attack requires a signature from a context where signing feels routine. Airdrop season is engineered for exactly that:

  • Users are trained to connect and sign on unfamiliar sites (testnet seasons are the training camp).
  • Claim flows already involve unfamiliar contract interactions, so an “authorization” step does not stand out.
  • Urgency (“claim window closing”) shortens the read-the-prompt phase to zero.

Fake claim pages and eligibility checkers thus became the natural carriers for 7702 payloads. The pattern to burn in: a claim that wants an “authorization” or “upgrade” signature is not a claim. Receiving tokens does not require delegating your account, ever.

What the prompt looks like — and how wallets responded

After the first exploits, wallet developers moved fast. MetaMask and other major wallets added dedicated 7702 warning UI: delegation payloads are flagged distinctly from ordinary transactions and signatures, typically surfacing the delegate address with explicit account-level language.

Your reading of the prompt, though, remains the control loop:

  1. The label. Any wording about authorization, delegation, upgrading, or adding code to your account — on a page you came to for an airdrop — is a takeover attempt. Full stop.
  2. The delegate address. If you are genuinely completing a 7702 flow with a wallet app you trust, verify the delegate against that app’s published documentation. On a claim site, there is nothing to verify against — which is the answer.
  3. The transaction shape. A legitimate claim is a call to a distributor contract. A batch that includes a delegation plus transfers you did not compose is attacker-authored code. If your wallet shows a multi-action batch you did not build, you are reading someone else’s plan for your account.

For the general discipline of reading prompts — function, spender, allowance, decodability — see airdrop signature scams and blind signing.

Defense: the same three layers, reweighted

The 7702 era does not change the defense stack; it raises the stakes on each layer:

  1. Isolation. The dedicated claim wallet from how to claim airdrops safely now matters more: a malicious delegate on an empty wallet delegates nothing. This layer alone converts the attack from catastrophic to irrelevant.
  2. Navigation discipline. The bookmark-the-official-URL habit from fake airdrop distribution channels keeps you off carrier pages entirely. Most 7702 victims never interacted with the real project at all — only its phishing clones.
  3. Prompt literacy. The signature taxonomy in airdrop signature scams now has a fifth member. Learn the smell of all five: approve, permit, Permit2, raw eth_sign, and delegation/7702.

One nuance worth keeping straight: 7702 itself is not a vulnerability in Ethereum — it is a capability with a sharp edge, like approvals before it. The incidents of 2025 were phishing incidents; the mechanism was the payload, not the cause. The same user discipline that defeats wallet drainers generally defeats this class.

If you signed something suspicious

The complete pre-claim check list — including the 7702-specific prompt read — is the airdrop safety checklist. This article is part of our Airdrop Safety series.

Frequently Asked Questions

What is EIP-7702 in simple terms?

It is a Pectra-upgrade feature that lets a regular Ethereum account (EOA) temporarily attach smart contract code to itself by signing a special authorization. The design goal is good: batching multiple actions into one transaction, paying gas with any token, social recovery. The risk: the same mechanism lets you delegate your account's powers to code you did not inspect — including an attacker's contract.

How was EIP-7702 used to steal funds?

The victim signed what appeared to be a routine interaction, but the payload included a 7702 authorization pointing at attacker-controlled code, followed by a batched transaction executed under the victim's account. Because the delegated code acts as the account itself, it can move assets that ordinary approval-based drainers cannot — without the victim sending anything from their wallet UI. Scam Sniffer documented the first such case on May 24, 2025, with a MetaMask user losing approximately $146,600.

How do I recognize a malicious EIP-7702 signature request?

Modern wallets display a distinct authorization banner for 7702 payloads — often labeling the delegate address and warning about account-level delegation. Treat any of the following as hostile on a claim or check page: an 'authorize' or 'upgrade' prompt you did not seek out, a delegation to an address you cannot verify, or raw undecoded data where a claim action should be. Legitimate airdrop claims almost never require delegating your account.

Does EIP-7702 make all EOAs unsafe?

No — delegation is opt-in per signature. An untouched EOA is unchanged. The risk only materializes when you sign a 7702 authorization, which is why the attack concentrates on contexts where people sign reflexively: airdrop claims, eligibility checkers, and mint pages. The feature is safe exactly as long as the signing discipline holds.

Can hardware wallets protect against 7702 phishing?

Only in the sense that they display what is being signed for you to read — they cannot override your decision to confirm. If you approve a delegation to attacker code on a device screen without reading it, the hardware executes it faithfully. The protection is the same as for approvals and permit signatures: understand the prompt before confirming, and keep claim interactions on a dedicated low-value wallet.