(Bloomberg) -- Johnson Controls Inc. fell the most in almost two months after disclosing that it’s dealing with a cyberattack that has caused disruptions in part of its internal information systems. 

Shares dropped as much as 5.7% Thursday morning, its biggest intraday decline since Aug. 2, though it pared losses later. For the year through Sept. 27, when the company announced the cyberattack in a filing after the market close, the shares have dropped 15%. The S&P 500 Index in that same period gained 11%. 

The company, which provide air-conditioning equipment and building security systems, is assessing what information was affected and has implemented workarounds to mitigate disruptions and continue servicing customers, Johnson Controls said in a statement. The company said it could be delayed in releasing its fiscal fourth quarter earnings as scheduled for Nov. 3.  

“The timing of JCI’s attack could not be worse, falling at the tail end of its most impactful quarter,” Nigel Coe, an analyst with Wolfe Research, wrote in a note. “The boilerplate disclosures that the operational impact cannot yet be assessed and that it is not clear if JCI can report timely 4QFY results (typically early-Nov) add another layer of complexity.” 

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