Hello. A man in his forties has been arrested in connection with a hack that has disrupted operations at big European airports since Sept. 19. He is out on bail and the investigation is ongoing, the U.K.'s National Crime Agency said Wednesday.

U.S. defense and aerospace company RTX on Wednesday acknowledged a "cybersecurity incident" affecting its passenger processing software in a disclosure to the Securities and Exchange Commission.

RTX's Collins Aerospace unit provides check-in and baggage systems shared by airlines at Heathrow, along with airports in Berlin, Brussels and Dublin, all of which have seen flight upsets for several days. 

"Our customers have shifted to back-up or manual processes and have experienced certain flight delays and cancellations," RTX said in an SEC filing.

Collins runs many lines of business, including doing tech modernization and systems security for the Federal Aviation Administration in the U.S., and generally accounts for about one-third of RTX's revenue.

RTX said it doesn't expect the incident to have a material impact on its business.

More news below.

• European Union tech watchdogs are chasing Apple, Booking.com, Google and Microsoft for information on how they are working to stem financial fraud on their platforms. That includes fake apps, deepfake video and audio, phishing schemes and other rackets. (Reuters)

Suspected Chinese espionage: Hackers linked to China's government have conducted a yearslong campaign to hack into U.S. law firms and tech companies in search of information about specific people and national-security data, according to Google cybersecurity researchers. The digital spies have also stolen source code to study for vulnerabilities, Google said. 

• Advanced malware known as Brickstorm has allowed the attackers to go undetected in target networks for an average of 393 days, Google said. (Cybersecurity Dive)

Gary Warzala, former CISO at Fifth Third Bank, PNC Bank and Visa, was appointed to the board of cyber company Defy Security. Warzala also sits on the board of First Financial Bank in Cincinnati.

The WSJ Pro Cybersecurity team is Deputy Bureau Chief Kim S. Nash and reporters Angus Loten, James Rundle and Catherine Stupp. Follow us on X @WSJCyber. Reach the team by replying to any newsletter you receive or by emailing Kim at kim.nash@wsj.com.