FedEx announced on June 28 its TNT Express subsidiary based in Europe was cyberattacked, which disrupted its operations and communications systems. The company said no data was breached, but the incident could have a material financial impact.
UBS lowered its rating for FedEx shares to neutral from buy, saying the company is facing market share losses in Europe due to the disruptions.
"We expect a combination of additional expense and lost revenue at TNT resulting from the cyber-attack to weigh on results throughout F2018," analyst Thomas Wadewitz wrote in a note to clients Friday.
"In addition, we do not yet have visibility to significant improvement in FDX's Ground margin which could provide an offset to the challenges at TNT."
The analyst cited how TNT had disruptions in their European service operations from June 28 to August 18. He noted the company "lost meaningful volumes in Express / Overnight area in particular" to other shipping competitors, according to his industry contacts.
"The TNT issues could indicate FDX may come in at the lower end of their [cost cutting] target or perhaps even below the low end (our F2020E now reflects about $1.0 bn of improvement)," he wrote.
FedEx did not immediately respond to a request for comment. Its shares traded roughly flat midday Friday after the report.
The delivery company's stock is up 15 percent year to date through Thursday versus the S&P 500's 11.5 percent return.
— CNBC's Michael Bloom contributed to this story.