https://smartcontractauditor.ai/assets/audit-chain-arbitrum-r0yS4Rxk.js

1import{j as e,aM as o,aQ as l,L as a,ay as r,m as c,l as d,x as i,S as m,Z as u,P as h,aw as p,B as x,ag as b}from"./index-DJZuVyTC.js";const f=[{type:"Sequencer Centralization Risk",severity:"High",description:"Arbitrum's sequencer is operated by Offchain Labs — a single centralized entity that orders transactions before they are submitted to Ethereum. A sequencer can frontrun user transactions, censor specific addresses, or go offline and halt L2 operations. Contracts that depend on transaction ordering guarantees or liveness are exposed to sequencer failure.",example:"A liquidation protocol that depends on liquidators being able to submit transactions within a specific time window — a sequencer outage (Arbitrum experienced a 7-hour outage in 2022) prevents liquidators from acting, creating bad debt."},{type:"Fraud Proof Window Attack",severity:"High",description:"Arbitrum One uses a 7-day optimistic rollup challenge period. During these 7 days, L2-to-L1 withdrawals are not final — a fraud proof can revert them. Contracts that depend on receiving Ethereum-side assets immediately after an L2 withdrawal transaction fail if a fraud proof challenge is submitted during the window.",example:"A protocol that atomically processes an L2 withdrawal and subsequent Ethereum-side operation — a fraud proof during the 7-day window reverts the L2 withdrawal, leaving the Ethereum-side operation completed without the corresponding L2 state change."},{type:"Arbitrum-Specific Precompile Differences",severity:"Medium",description:"Arbitrum implements several Ethereum precompiles differently or adds Arbitrum-specific precompiles (ArbSys, ArbGasInfo). Contracts that interact with these precompiles or assume Ethereum L1 precompile behavior may behave unexpectedly on Arbitrum. ArbSys.arbBlockNumber() returns Arbitrum block numbers, not Ethereum block numbers — a significant difference for time-dependent logic.",example:"A contract using block.number for time-based vesting — on Arbitrum, block.number returns the Arbitrum block (which advances much faster than Ethereum), causing vesting schedules to complete far earlier than intended."},{type:"L1-to-L2 Message Delay Exploitation",severity:"Medium",description:"Arbitrum's inbox mechanism introduces a delay between L1 message submission and L2 execution. Contracts that depend on immediate cross-chain message processing can be exploited if an attacker can submit a conflicting L2 transaction during the delay window — settling a dispute differently than the L1 message intended.",example:"A cross-chain governance contract that accepts votes via L1 messages — a 10-minute delay in L1-to-L2 message processing allows a different on-chain state to be established during the delay window."},{type:"Gas Estimation Inaccuracy",severity:"Low",description:"Arbitrum's two-dimensional gas model (L2 execution gas + L1 data posting gas) makes gas estimation more complex than Ethereum. Contracts that perform gas checks or provide gas estimates to users may produce incorrect values if they don't account for both gas dimensions, leading to failed transactions or user confusion.",example:"A meta-transaction relayer that estimates gas for users and fronts the cost — the relayer underestimates L1 data posting fees, pays more than it charges, and becomes unprofitable over time."}],n=[{q:"What is Arbitrum and how is it different from Ethereum for smart contract security?",a:"Arbitrum One is an optimistic rollup that settles to Ethereum — transactions are processed off-chain by Arbitrum's sequencer, batched, and submitted to Ethereum as calldata. The 'optimistic' model assumes transactions are valid and uses a 7-day fraud proof challenge period for security. Arbitrum Nova is a separate chain using AnyTrust for data availability. For smart contract security, Arbitrum contracts face all of Ethereum's Solidity vulnerability classes plus Arbitrum-specific concerns: sequencer centralization, fraud proof timing, block.number semantics, and L1-to-L2 message delays."},{q:"What was the Arbitrum outage in 2022 and what does it mean for security?",a:"In January 2022, Arbitrum experienced a 7-hour sequencer outage due to a bug that caused the sequencer to get stuck processing a high-volume period. During the outage, the L2 was unable to process transactions. While user funds were never at risk (the L1 bridge remained intact), DeFi protocols depen

1dent on liquidations or time-sensitive operations were unable to function. The incident demonstrates the risk of depending on a single centralized sequencer — a risk that Arbitrum has been gradually decentralizing through the Arbitrum DAO."},{q:"Is Arbitrum Nova different from Arbitrum One for security purposes?",a:"Yes. Arbitrum One uses a full optimistic rollup model with Ethereum for data availability — the strongest security model. Arbitrum Nova uses AnyTrust, where a Data Availability Committee (DAC) of 20 parties agrees to maintain transaction data, with Ethereum as a fallback. Nova's security model requires trusting at least one honest DAC member rather than trusting Ethereum alone. For high-security DeFi contracts, Arbitrum One provides stronger security guarantees than Nova. Nova's lower transaction costs are better suited for high-frequency, lower-security applications like gaming and social."},{q:"How does the 7-day withdrawal window affect Arbitrum DeFi protocols?",a:"The 7-day optimistic challenge window affects any protocol that bridges assets from Arbitrum to Ethereum. Users must wait 7 days for withdrawals to finalize — which affects liquidity, treasury management, and any protocol that assumes immediate cross-chain asset availability. Fast bridges (Hop Protocol, Across, Stargate) solve the UX problem by fronting liquidity, but introduce their own bridge security risks. Smart contracts that need to atomically process an L2 withdrawal and L1 operation must account for the 7-day gap."},{q:"How much does an Arbitrum smart contract audit cost?",a:"Arbitrum contracts use the same Solidity codebase as Ethereum — most audits price Arbitrum deployments identically to Ethereum L1 deployments, with an L2-specific review added for sequencer assumptions, block.number semantics, and cross-chain message handling. Full audit cost: $5k–$300k depending on complexity. SmartContractAuditor.ai analyzes Arbitrum contracts for all EVM vulnerability classes plus Arbitrum-specific patterns — free for the first scan."}],g={"@context":"https://schema.org","@graph":[{"@type":"Article",headline:"Arbitrum Smart Contract Audit — Optimistic Rollup Security",description:"AI-powered security audit for Arbitrum smart contracts. Optimistic rollup fraud proof assumptions, sequencer centralization risks, 7-day withdrawal window, and L2-specific Solidity patterns.",url:"https://smartcontractauditor.ai/audit/arbitrum",datePublished:"2026-01-01",dateModified:"2026-07-31",author:{"@type":"Person",name:"Duron Epps",jobTitle:"Founder",url:"https://smartcontractauditor.ai"},publisher:{"@type":"Organization",name:"SmartContractAuditor.ai",url:"https://smartcontractauditor.ai"}},{"@type":"FAQPage",mainEntity:n.map(t=>({"@type":"Question",name:t.q,acceptedAnswer:{"@type":"Answer",text:t.a}}))}]};function w(){return e.jsxs(e.Fragment,{children:[e.jsx(o,{title:"Arbitrum Smart Contract Audit — Optimistic Rollup Security | SmartContractAuditor.ai",description:"AI-powered audit for Arbitrum smart contracts. Sequencer centralization, 7-day fraud proof window, L2 block number semantics — free first scan.",canonicalUrl:"https://smartcontractauditor.ai/audit/arbitrum",keywords:"Arbitrum smart contract audit, Arbitrum One security, Arbitrum DeFi audit, optimistic rollup security, L2 smart contract audit",structuredData:g}),e.jsxs("div",{className:"min-h-screen bg-[#080a12] text-white",children:[e.jsx(l,{}),e.jsx("div",{className:"border-b border-slate-800",children:e.jsx("div",{className:"max-w-5xl mx-auto px-6 py-3",children:e.jsxs("nav",{className:"flex items-center gap-2 text-sm text-slate-400",children:[e.jsx(a,{href:"/",className:"hover:text-white",children:"Home"}),e.jsx(r,{className:"w-4 h-4"}),e.jsx(a,{href:"/smart-contract-audit",className:"hover:text-white",children:"Audit"}),e.jsx(r,{className:"w-4 h-4"}),e.jsx("span",{className:"text-slate-200",children:"Arbitrum"})]})})}),e.jsx("section",{className:"max-w-5xl mx-auto px-6 pt-14 pb-10",children:e.jsxs(c.div,{initial:{opacity:0,y:30},animate:{opacity:1,y:0},transition:{duration:.5},children:[e.jsx(d,{className:"mb-4 bg-sky-500/20 text-sky-300 border-sky-500/30 text-xs",children:"Arbitrum · Optimistic Rollup · L2 · EVM-Equivalent"}),e.jsx("h1",{className:"text-4xl md:text-5xl font-extrabold bg-gradient-to-r from-white to-slate-400 bg-clip-text text-transparent mb-5",children:"Arbitrum Smart Contract Audit"}),e.jsxs("div",{className:"relative bg-slate-800/40 border border-slate-700/50 rounded-2xl p-6 mb-8 overflow-hidden",children:[e.jsx("div",{className:"absolute left-0 top-0 bottom-0 w-1 rounded-l-2xl bg-gradient-to-b from-emerald-400 to-emerald-600"}),e.jsx("p",{className:"text-sm text-emerald-400 font-semibold uppercase tracking-wide mb-3",children:"Qu

1ick Answer"}),e.jsxs("ul",{className:"space-y-2 text-slate-200",children:[e.jsxs("li",{className:"flex items-start gap-2",children:[e.jsx(i,{className:"w-4 h-4 text-emerald-400 mt-0.5 shrink-0"}),e.jsx("span",{children:"Arbitrum is an optimistic rollup — transactions are processed off-chain and submitted to Ethereum with a 7-day fraud proof challenge window. All Ethereum Solidity vulnerabilities apply, with Arbitrum-specific risks: centralized sequencer, block.number semantics (advances faster than Ethereum), and L1-to-L2 message delay."})]}),e.jsxs("li",{className:"flex items-start gap-2",children:[e.jsx(i,{className:"w-4 h-4 text-emerald-400 mt-0.5 shrink-0"}),e.jsx("span",{children:"Arbitrum experienced a 7-hour sequencer outage in January 2022 — demonstrating that DeFi protocols dependent on liquidations or time-sensitive operations face centralization risk from the single Offchain Labs sequencer."})]}),e.jsxs("li",{className:"flex items-start gap-2",children:[e.jsx(i,{className:"w-4 h-4 text-emerald-400 mt-0.5 shrink-0"}),e.jsx("span",{children:"Arbitrum is one of Ethereum's largest L2s by TVL ($2B+). Exchange listings and institutional investment require security audit documentation. Free first scan, results in 60 seconds."})]})]})]}),e.jsx("p",{className:"text-lg text-slate-300 leading-relaxed",children:"Arbitrum's EVM equivalence means Ethereum security patterns apply directly — the additional audit surface is Arbitrum's optimistic rollup assumptions, sequencer trust model, and L2-specific precompile behavior."})]})}),e.jsxs("section",{className:"max-w-5xl mx-auto px-6 pb-12",children:[e.jsx("h2",{className:"text-2xl font-bold mb-6",children:"Arbitrum-Specific Security Considerations"}),e.jsx("div",{className:"grid md:grid-cols-2 gap-4",children:[{icon:e.jsx(m,{className:"w-5 h-5 text-sky-400"}),title:"Sequencer Trust Assumption",body:"Arbitrum's sequencer is a single centralized entity. It can frontrun, censor, or halt. Contracts that require sequencer liveness guarantees or assume fair transaction ordering are exposed to sequencer failure or manipulation."},{icon:e.jsx(u,{className:"w-5 h-5 text-yellow-400"}),title:"7-Day Withdrawal Finality",body:"L2-to-L1 withdrawals take 7 days to finalize. Contracts that need immediate Ethereum-side asset availability after an Arbitrum withdrawal must use bridging protocols — introducing additional bridge security risk."},{icon:e.jsx(h,{className:"w-5 h-5 text-blue-400"}),title:"block.number Semantics",body:"block.number on Arbitrum returns Arbitrum block numbers, not Ethereum block numbers. Arbitrum produces blocks much faster than Ethereum — time-dependent contracts using block.number behave differently than intended."},{icon:e.jsx(p,{className:"w-5 h-5 text-emerald-400"}),title:"L1-to-L2 Message Delays",body:"Cross-chain messages from Ethereum to Arbitrum have a processing delay. Contracts that depend on immediate L1-to-L2 message execution can face race conditions during the delay window."}].map(t=>e.jsxs("div",{className:"bg-slate-800/40 border border-slate-700 rounded-2xl p-5",children:[e.jsxs("div",{className:"flex items-center gap-3 mb-2",children:[t.icon,e.jsx("h3",{className:"font-semibold text-white",children:t.title})]}),e.jsx("p",{className:"text-slate-300 text-sm leading-relaxed",children:t.body})]},t.title))})]}),e.jsx("section",{className:"max-w-5xl mx-auto px-6 pb-12",children:e.jsxs("div",{className:"bg-emerald-950/40 border border-emerald-700/40 rounded-2xl p-8 text-center",children:[e.jsx("h2",{className:"text-2xl font-bold mb-3",children:"Audit Your Arbitrum Contract Now"}),e.jsx("p",{className:"text-slate-300 mb-6",children:"Sequencer trust, fraud proof timing, L2 semantics, Solidity vulnerabilities — free first scan."}),e.jsx(a,{href:"/smart-contract-audit",children:e.jsxs(x,{size:"lg",className:"bg-emerald-500 hover:bg-emerald-400 text-black font-semibold px-8",children:["Start Free Arbitrum Audit ",e.jsx(b,{className:"ml-2 w-4 h-4"})]})})]})}),e.jsxs("section",{className:"max-w-5xl mx-auto px-6 pb-12",children:[e.jsx("h2",{className:"text-2xl font-bold mb-6",children:"Arbitrum Vulnerability Classes"}),e.jsx("div",{className:"overflow-x-auto",children:e.jsxs("table",{className:"w-full text-sm border-collapse",children:[e.jsx("thead",{children:e.jsxs("tr",{className:"border-b border-slate-700",children:[e.jsx("th",{className:"text-left py-3 px-4 text-slate-400 font-medium",children:"Vulnerability"}),e.jsx("th",{className:"text-left py-3 px-4 text-slate-400 font-medium",children:"Severity"}),e.jsx("th",{className:"text-left py-3 px-4 text-slate-400 font-medium",children:"Description"}),e.jsx("th",{className:"text-left py-3 px-4 text-slate-400 font-medium",children:"Example"})]})}),e.jsx("tbody",{children:f.map((t,s)=>e.jsxs("tr",{className:"border-b border-slate-800 hover:bg-slate-800/30",children:[e.jsx("td",{className:"py-4 px-4 font-medium text-white align-top",children:t.type}),e.jsx("td",{className:"py-4 px-4 align-top",children:e.jsx("span",{className:`text-xs font-semibold px-2 py-1 rounded ${t.severity==="High"?"bg-orange-500/20 text-orange-300":t.severity==="Medium"?"bg-yellow-500/20 text-yellow-300":"bg-slate-500/20 text-slate-300"}`,children:t.severity})}),e.jsx("td",{className:"py-4 px-4 text-slate-300 align-top text-sm",children:t.description}),e.jsx("td",{className:"py-4 px-4 text-slate-400 text-xs italic align-top",children:t.example})]},s))})]})})]}),e.jsxs("section",{className:"max-w-5xl mx-auto px-6 pb-12",children:[e.jsx("h2",{className:"text-2xl font-bold mb-6",children:"Arbitrum Audit — FAQs"}),e.jsx("div",{className:"space-y-3",children:n.map((t,s)=>e.jsxs("details",{className:"bg-slate-900/50 border border-slate-800/80 rounded-2xl overflow-hidden group hover:border-slate-700 transition-colors",children:[e.jsxs("summary",{className:"flex items-center justify-between p-5 cursor-pointer font-medium text-white list-none",children:[t.q,e.jsx(r,{className:"w-4 h-4 text-slate-400 group-open:rotate-90 transition-transform shrink-0 ml-3"})]}),e.jsx("div",{className:"px-5 pb-5 text-slate-300 leading-relaxed text-sm",children:t.a})]},s))})]}),e.jsxs("section",{className:"max-w-5xl mx-auto px-6 pb-12",children:[e.jsxs("div",{className:"border-t border-slate-800 pt-6 text-sm text-slate-400",children:["Written by ",e.jsx("span",{className:"text-slate-200 font-medium",children:"Duron Epps"}

1),", Founder of SmartContractAuditor.ai · Last updated July 2026"]}),e.jsxs("div",{className:"mt-4 flex flex-wrap gap-3 text-sm",children:[e.jsx(a,{href:"/bridge-security-audit",className:"text-emerald-400 hover:underline",children:"Bridge Security"}),e.jsx("span",{className:"text-slate-700",children:"·"}),e.jsx(a,{href:"/defi-audit",className:"text-emerald-400 hover:underline",children:"DeFi Audit"}),e.jsx("span",{className:"text-slate-700",children:"·"}),e.jsx(a,{href:"/audit/base",className:"text-emerald-400 hover:underline",children:"Base Audit"}),e.jsx("span",{className:"text-slate-700",children:"·"}),e.jsx(a,{href:"/smart-contract-audit-cost",className:"text-emerald-400 hover:underline",children:"Audit Pricing"})]})]})]})]})}export{w as default};