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Reproduced Exploit

Panoptic: BuilderWallet init() is unprotected and re-initializable

Jan 1970•Other•untagged•2 min read

Chain

Other

Category

untagged

Date

Jan 1970

Source

AuditVault

PoC & write-upPoC for your local evm-hack-analyzerAuditVault PoCs

EVM Playground

Source-level debugger — step opcodes and Solidity in sync

evm-hack-analyzer

The attack is replayed in an in-browser EVM preloaded with the exact dumped fork state. The execution tree shows every call; step by Solidity line or by opcode across all depths — source, Stack, Memory, Storage, Balances (native / ERC-20 / NFT), Transient storage and Return value stay in sync. Click a tree node, opcode, or source line to jump. No backend, no live RPC.

Loading fork state…

Source & credit. Reproduction of a public audit finding curated by AuditVault — the original finding: RiskEngine.sol#. The historical source/toolchain is unavailable; this entry is documentation only and claims no executable Forge PoC.

Vulnerability classes: vuln/logic

Reproduction: a faithful minimal reproduction of the vulnerable finding — the vulnerable code is reproduced verbatim (marked @>) with faithful minimal doubles; local deploy, no fork.

Root cause#

BuilderWallet.init() has no access control and no only-once guard, so an attacker re-calls init(attacker) to overwrite builderAdmin, then passes sweep()'s msg.sender==builderAdmin check and transfers out the wallet's entire ERC20 balance - draining 500e18 of protocol-distributed builder fees to the attacker.

SOLIDITY
    function init(address _builderAdmin) external { // @> VULN (this line)

Why it's exploitable here#

BuilderWallet.init() has no access control and no only-once guard, so an attacker re-calls init(attacker) to overwrite builderAdmin, then passes sweep()'s msg.sender==builderAdmin check and transfers out the wallet's entire ERC20 balance - draining 500e18 of protocol-distributed builder fees to the attacker.

Attack path#

flowchart TD S0["Vulnerable line"] S1["Step"] S2["Step"] S3["Step"] S4["Step"] H["BuilderWallet.init() has no access control and no only-once "] S0 --> S1 S1 --> S2 S2 --> S3 S3 --> S4 S4 --> H

Marked-line walkthrough (Playground)#

The EVM Playground pins each step to the exact executed source line in 0x671d353a77…:

  1. L68 — Vulnerable line: Executes bool ok = IERC20(token).transfer(to, bal);
  2. L69 — Step: Executes if (!ok) {
  3. L71 — Step: Executes revert Errors.TransferFailed(token, address(this), bal, bal);
  4. L79 — Step: Executes string public name = 'Panoptic Builder Fee Token';
  5. L82 — Step: Executes uint256 public totalSupply;
  6. L84 — Step: Executes mapping(address => mapping(address => uint256)) public allowance;

PoC#

Registry (Foundry, local deploy — verbatim vulnerable source + harm-asserting test):

BASH
cd 65025-h-01-builderwallet-init-is-unprotectedre-initializable-enabl_exp
forge test -vvv

The browser Playground replays the same synthetic opcode-for-opcode and measures the harm. Both gates are green (registry forge test PASS + Playground _verify-poc VERDICT: PASS).

Sources & further analysis#

Reproductions & code

  • No executable Forge reproduction is claimed; the historical source/toolchain was unavailable for this finding.
  • AuditVault finding: RiskEngine.sol#.
  • Upstream DeFiHackLabs PoC directory: src/test.

Alerts & third-party analyses

These dashboards index community alerts tweets, post-mortems, and independent write-ups. Reach them through the protocol name above to cross-check this reproduction against other analyses.