Used external hard drives selling as new on Amazon, data recovery firm warns

Popular UnionSine external hard drives sold as new on Amazon were actually used for up to 10 years before, a new report by Attingo Datenrettung, a German data recovery firm, has warned. They could even restore the old data.

The firm itself became a victim of consumer deception practices. During a Tech Week event in May, the firm bought several external USB hard drives from UnionSine through its marketplace shop as part of a routine spare parts purchase.

However, Attingo data recovery experts were “shocked” when they analyzed the goods. Instead of new hardware, they found that some disks had been used for up to 10 years, and the data could still be recovered.

“The fact that this is now happening in this systematic way as part of a widely advertised Amazon campaign is truly scandalous,” warns Markus Häfele, Managing Director of Attingo Datenrettung, in a report.

“This practice is highly problematic both from a data protection and operational security perspective. The devices are technically unreliable and potentially contaminated with sensitive legacy data from third parties.”

To this day, UnionSine external drives have accumulated over 52 thousand customer reviews, most of which are very positive, averaging at 4.5 stars. “UnionSine-DE” is listed as the seller.

At the time of writing, prices for the device range from around 27 euros ($31) for a 320GB option to 71.29 euros ($82.38) for a 2TB model. These external hard drives use older mechanical 2.5-inch tech: a spinning platter instead of memory cells commonly found in SSDs.

Wear and manipulated SMART values

The purchased UnionSine HD2510 had recent production dates – March or April 2025 – written on the casing. However, the serial numbers and firmware versions reveal that the HDDs came from Seagate or Western Digital, from production batches that were more than 10 years old.

“In the test cases, 40 to 80 percent of them were filled with raw data, only the beginning was overwritten with 0x00,” the report translation reads.

“In each specific case, the data was video data from proprietary TV recording systems. The partially reconstructable XML files within the raw data showed timestamps from May 2024 and contained indications that the hard drives had been fully used, except for a few MB.”

The data recovery exports also discovered anomalies in the disk drives' SMART (self-monitoring, analysis, and reporting technology) values. SMART is used to monitor the health and reliability of the drive.

One of the drives had anomalies and errors, such as indicating physically faulty sectors during reading (Raw_Read_Error_Rate), repeated errors when positioning the electromagnetic head that reads and writes data to the disk plates (Seek_Error_Rate), or shocks or vibrations registered by the drive (G-Sense_Error_Rate).

However, some hard drive parameters were deliberately manipulated to conceal their use. The experts found that the number of start/stop cycles (Start_Stop_Count) was reset to 1, and the operating hours (Power_On_Hours) value was reset to 0.

“This suggests a systematic attempt to sell used drives as new,” the report reads.

The devices' formatting and partitioning were also inconsistent: some drives were labeled “External HD,” others were named “UnionSine.” All file systems were exFat, and metadata revealed formatting as early as January 2024, months before the timestamps on drives.

It’s not the first time in Germany that experts have found old storage devices packaged as new ones on major marketplaces. Many legitimate retailers sent customers used Seagate internal hard drives that had accumulated significant hours.

Attingo says that these practices have been a constant concern for years.

“We also frequently receive memory cards and USB sticks with alleged storage capacities that often exceed industry standards. These ‘no-name’ storage devices were usually purchased at unbeatable prices,” the firm said.

Customers risk losing their data even after a single use. Therefore, security experts advise against using dubious external storage media for sensitive data without proper device checks, especially with suspiciously cheap offers.