Swap Security 101: Why Your Destination Address Can't Be Changed Mid-Swap
The specific address-substitution attack this protects against, and how every swap is re-verified against the real on-chain result.
Cross-chain swaps move value between systems that can't directly see each other (see how a cross-chain swap actually works if you're new to the mechanism) — which is exactly the kind of gap an attacker looks for. One of the most common real-world exploits in bridging/swapping tools is address substitution: something in the pipeline (a compromised frontend, a man-in-the-middle on the request, a race condition in a backend) swaps out the destination address between the moment you approve a swap and the moment it actually executes.
How Blockchains.Click closes that gap
The destination address you provide is locked in at the moment you get a quote — baked into the quote itself, not passed around as a separate mutable field later in the flow. It cannot be altered afterward on either the frontend or the backend. There's no code path, intentional or accidental, that lets a later step in the pipeline substitute a different address than the one you approved.
Verification doesn't stop at "the transaction was sent"
A lot of swap tools consider their job done once a transaction hash comes back from the client. That's not enough — a client can lie, or a transaction can partially fail in a way that still returns a hash. Every buy transaction on Blockchains.Click is independently re-verified against the real, on-chain result before it's ever marked complete. If what actually landed on-chain doesn't match what was quoted, it isn't silently accepted as a success.
What this means for you practically
You don't need to do anything differently — this protection is structural, not a setting you opt into. The one thing worth double-checking yourself: make sure the destination wallet address you enter is correct before confirming, since that's the one part of the flow that's genuinely under your control and can't be verified by the system on your behalf.
Read more
Curious about the fee structure, or how points and referrals work? Check our FAQ — every answer there is grounded in how the app actually behaves today, not aspirational copy.