A new report alleging Intel chips have a security flaw is moving semiconductor stocks.

The Register reported Tuesday some Intel processors have a “fundamental design flaw” that will spur a significant security update of Linux and Microsoft Windows operating systems to work around it.

Shares of AMD rose 7 percent during Wednesday’s premarket session following the report, while Intel’s stock declined 2 percent

“Programmers are scrambling to overhaul the open-source Linux kernel’s virtual memory system,” the report said. “Crucially, these updates to both Linux and Windows will incur a performance hit on Intel products.”

The Register cited a post from an AMD employee which implied the company’s chips are “not affected” by this particular security issue.

AMD declined to comment on the report. Intel did not immediately respond to a request for comment.

Intel shares rose 27 percent in 2017 versus AMD’s stock 9 percent decline.