CrowdStrike CRWD.O said on Sunday in a response to Delta Airlines DAL.N that the cybersecurity firm should not be blamed for the carrier's flight disruptions following the July 19 global outage that crashed more than 8 million computers.

CrowdStrike reiterated its apology to the airline operator, and said in a letter that it is "highly disappointed by Delta's suggestion that CrowdStrike acted inappropriately and strongly rejects any allegation that it was grossly negligent or committed misconduct."