A dump is stolen magnetic-stripe data, taken through skimming or breaches and sold in criminal markets to be encoded onto fake cards. It is the raw material for in-person cloning fraud, the ingredient a counterfeiter needs before a single fake card exists.
What is a dump, in plain English?
A dump is the block of data that lives on a card's magnetic stripe, stolen and packaged for sale. It contains the account number, expiry, and the encoded track data a terminal reads when a card is swiped. On its own it is just a string of characters, but encoded onto a blank card it becomes spendable at any store that still accepts a swipe.
Criminals harvest dumps through skimmers on ATMs and fuel pumps, point-of-sale malware, and large merchant breaches. The data then flows into criminal markets where it is listed for sale, priced and sorted so buyers can shop for exactly the cards they want.
In the fraud supply chain, the dump is the upstream product. A data thief steals it, a market sells it, and a counterfeiter turns it into cards. Understanding dumps is really about understanding where card-present fraud begins.
Dumps versus fullz
What changes | Dump | Fullz |
What it contains | Magnetic-stripe track data only | A full identity: name, address, date of birth, ID or SSN, and financial data |
Main use | Cloning cards for in-person spending | Account takeover, new-account and synthetic-identity fraud |
Where it works | Card-present, at swipe terminals | Card-not-present and application channels |
Relative price | Cheaper, sold in bulk by card range | More expensive, unlocks higher-value fraud |
What it looks like in practice
In practice
A fraud analyst at an issuer notices a wave of counterfeit spending, and every affected card was used weeks earlier at the same regional grocery chain. On a criminal market, fresh dumps tagged with that chain's card ranges are being sold in batches, sorted by issuer and region and priced higher because the data is recent.
The shared point of purchase confirms the grocery chain was breached and its stripe data is now feeding dumps to encoders. The issuer moves fast, reissuing the exposed card ranges and tightening magstripe fallback rules before the buyers can cash out the whole batch.
Why it matters to operators
Dumps are the signal that a breach has already happened and is now monetizing. When a batch of fraud shares one common point of purchase, that earlier merchant is almost always the source, and finding it quickly lets a team reissue exposed cards before the whole batch is spent. The dump market is, in effect, an early-warning feed if you know how to read it.
Because dumps are card-present material, the defense is different from online fraud. Chip technology neutralizes static stripe data at the terminal, so the residual risk concentrates in magstripe fallback and non-chip corridors. Knowing that a term is a dump rather than fullz tells you exactly which channel is under threat.
What to watch in the data
- Common point of purchase. A cluster of fraud where all cards touched one earlier merchant usually means that merchant fed the dumps.
- Fallback swipes. Chip cards being swiped by stripe, the way cloned dump data is spent, is a direct tell.
- Card-range concentration. Fraud clustering on specific card ranges can match a batch of dumps listed for those issuers.
- Freshness pricing. Newly breached data sells at a premium, so a spike often follows a recent, still-unannounced breach.
- Card-present, impossible geography. In-person use far from the cardholder's real location is the classic cloned-card footprint.
Quick questions
What is the difference between a dump and fullz?
A dump is just the card's stripe data, useful for cloning cards to spend in person. Fullz is a complete stolen identity that unlocks account takeover and new-account fraud. Dumps are cheaper and narrower.
How do criminals get dumps?
Mainly through skimmers on ATMs and fuel pumps, malware on point-of-sale systems, and breaches of merchants that stored or transmitted stripe data. The captured tracks are then packaged and sold.
Why are dumps priced by card range and region?
Buyers want cards that will work where they plan to cash out and that come from issuers with looser controls. Sorting by range, issuer, region, and freshness lets them shop for the most usable data.
Does EMV stop dump fraud?
Largely, in chip markets. EMV creates a one-time code per transaction, so static stripe data no longer works at a chip terminal. The leftover risk sits in fallback swipes and non-chip regions.
How does a dump become a usable card?
A buyer encodes the track data onto a blank or reused card with a simple encoder. That counterfeit card is then swiped at stores or ATMs to buy goods or withdraw cash.
Can spotting dumps help prevent fraud?
Yes. If a team can tie a fraud cluster to a common point of purchase, it can identify the breached merchant and reissue the exposed cards before the dumps are fully monetized.
Go deeper
- EMVCo ↗ — Maintains the EMV chip and 3-D Secure specifications for card payments.
- PCI Security Standards Council ↗ — Security standards for handling cardholder data, including PCI DSS.