Verifone Systems is investigating a breach of its internal networks that appears to have impacted a number of companies running its point-of-sale card terminals, Krebs on Security said in a blog post citing sources.
Shares of the Payment card machine maker were down 2.7% at $19.89 in afternoon trading on Tuesday.
"Verifone says the extent of the breach was limited to its corporate network and that its payment services network was not impacted," according to the report on Tuesday.
"We are currently investigating an IT control matter in the Verifone environment," a Verifone executive said in an internal memo posted on the blog.
On Jan. 23, Verifone (pay) sent an urgent email to staff and contractors, warning they had 24 hours to change all company passwords, according to the blog.
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Verifone, Mastercard, and Visa did not immediately respond to requests for comment.