ChainBleedv0.1 · open intel
← back to feed·FRONTEND2026-04-14 · 1mo ago
Incident · SLOWMIST

CowSwap

Supply-chain attack
Estimated loss
$1.20M
VERDICT —OUT OF SCOPE
Root cause is a frontend / UI hijack — users authorized the malicious transaction from a compromised site or DNS. On-chain contract was not the failure surface; pre-deployment audit cannot catch this class.
▰ METHOD
FRONTEND
FRONTEND
Root cause

Root-cause analysis not yet published. The incident description below contains all currently available signal — review the attack transaction directly for definitive forensics.

Forensic narrative

Blockchain security firm Blockaid reported that its system has detected a front-end attack on the decentralized exchange CoW Swap, and that cow.fi has been flagged as a malicious site. Blockaid warned that users who have previously connected their wallets to CoW Swap should immediately revoke any related contract approvals via their wallets or security tools, and refrain from interacting with cow.fi until the issue is resolved to prevent potential asset loss. Subsequently, CoW DAO issued a statement confirming that the CoW Swap front end (swap.cow.fi) is currently experiencing issues. The team is actively investigating and advised users to temporarily avoid using the platform for trading. On April 16, it was reported that CoW Swap announced on X (formerly Twitter) that it has regained control of the cow.fi domain and has been operating normally on cow.finance for some time. The platform is now gradually transitioning back to its original domain. Attack method (per SlowMist): Supply-chain attack. Reported loss: $ 1,200,000.

Primary source
https://x.com/CoWSwap/status/2044089359058501893
Sourced from
slowmist
Technical record
chain
protocol
CowSwap
bug_class
frontend
date_occurred
2026-04-14
loss_usd
$1,200,000
source_id
sm:cowswap::2026-04-14
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