
Briefing
A high-profile token launch on the Base network was immediately compromised by sophisticated actors utilizing same-block transaction sniping, resulting in the predatory acquisition of 26% of the total token supply. This systemic economic exploit was executed by leveraging Base’s ultra-fast 200-millisecond block times and submitting highly aggressive, high-fee transactions to front-run retail liquidity. The primary consequence is the immediate erosion of fair distribution and a major loss of confidence in the launch mechanism, with two primary snipers confirmed to have netted over $1.3 million in combined profit by exploiting the chain’s technical architecture.

Context
The prevailing risk factor in token launches is the “sniping” or front-running of initial liquidity provisioning, a class of vulnerability that existed prior to this incident. While smart contracts were not breached, the attack surface was the underlying blockchain’s transaction ordering mechanism. The rapid block finality of high-throughput Layer 2 solutions, designed for speed, inadvertently created a prime environment for this specific form of maximal extractable value (MEV) by compressing the window for fair participation.

Analysis
The attack vector was the exploitation of the Base chain’s fast block production to execute a “same-block” transaction pattern. The attacker first monitored the mempool for the token’s initial liquidity provisioning transaction. Immediately upon detecting the launch, the actor submitted a massive buy order with an exceptionally high gas fee ∞ a Priority Gas Auction (PGA) ∞ to ensure their transaction was processed in the exact same block as the liquidity addition, or immediately before any retail users.
This allowed the snipers to purchase a quarter of the supply at the lowest possible initial price, creating an artificial price spike and securing an instant, massive, and asymmetric profit before the market could react. This is a systemic failure of fair launch mechanics.

Parameters
- Total Quantified Sniping Profit ∞ $1.3 Million – The minimum estimated profit secured by the two most successful front-running wallets.
- Compromised Supply Percentage ∞ 26% – The portion of the total token supply secured by sniping bots at launch.
- Exploited Architecture Parameter ∞ 200 Milliseconds – The block time on the Base network that enabled the same-block transaction finality.
- Highest Gas Fee Bid ∞ $44,000 – The amount spent on sequencer fees by one actor to guarantee inclusion in the target block.

Outlook
Immediate mitigation for future launches requires protocols to adopt sophisticated anti-sniping mechanisms, such as Dutch auctions or time-weighted average price (TWAP) distribution models, to neutralize the advantage of rapid block inclusion. This incident establishes a new security best practice ∞ the economic design of a token launch must be treated as an attack surface, not just the smart contract code. The contagion risk is high, as all Layer 2 solutions with fast block times are now confirmed to be vulnerable to this high-capital, low-risk sniping strategy, necessitating a systemic review of transaction ordering guarantees.
