When people leave the checkout at their favorite stores, they tend to put the whole experience of paying behind them. However, the recently discovered PoSeidon malware shows that cybercriminals are deeply interested in the data long after receipts are put in the bag.

First discovered by researchers at Cisco Systems, the PoSeidon malware attempts to scrape point-of-sale (POS) systems at retail locations for customers’ personal information. This could include credit card data, which is scraped by keylogging software that looks through a POS system’s memory. Full details of how the malicious software works were detailed in a blog post from Cisco.

After major data security breaches at high-profile retailers such as Target and Home Depot over the past year, concerns around IT security are probably already at an all-time high. However, the PoSeidon malware may be worse than the usual threats, Computerworld reported. This is because it includes several components that let it stay installed, even if a POS system gets rebooted and has the ability to connect with off-site computer systems that let it receive updates, much like legitimate software.

As InfoSecurity Magazine pointed out, the PoSeidon malware may be particularly worrisome for merchants in the United States, where the adoption of chip and PIN technology that could help fend off such attacks is still in its early stages. Though the use of magnetic strips on credit cards is expected to decline later this year to comply with regulatory standards, that still leaves a large window of opportunity for cybercriminal exploits in the meantime.

Far from being deterred by increased retailer vigilance, cybercriminals are not merely using the same old tricks, but rather building upon the work of their peers, experts suggest. For example, The Register described the PoSeidon malware as the next generation of Zeus, an exploit kit that surfaced last year, and the BlackPOS malware used in last year’s Target attack. Consequently, it may be difficult for chief security officers and their teams to easily take apart the latest forms of malicious software to better understand them.

There were few details on the extent to which this particular threat has been deployed across POS systems, but ComputerWeekly suggested potential victims could come in all shapes and sizes. The stolen data could then be resold by cybercriminals for financial gain. If awareness around these types of problems rises, high prices alone won’t be the only thing that makes consumers think twice about making their way to a cash register.