By Cristina Gallardo

European airports affected by a weekend cyberattack said work was continuing to resolve and recover from an outage that caused flight delays and cancellations.

Four of Europe's main airports and airlines that operate there became the latest victims of a series of cyberattacks against Western companies that in recent months also hit car, luxury and retail companies.

The cyberattack hit the check-in and boarding systems used by London's Heathrow airport, Berlin Brandenburg Airport, Brussels Airport and Dublin Airport.

The software was provided by Collins Aerospace, a subsidiary of U.S. aerospace and defense manufacturer RTX, which on Monday said it was working with the affected airports on the final stages of completing the updates needed to restore its systems back to full functionality.

Heathrow Airport said airlines operating from there had implemented contingencies, meaning that the majority of flights were operating as normal, although check-in and boarding for some flights might take slightly longer than usual.

Brussels Airport said 40 out of 277 departing flights scheduled for Monday had been canceled, as well as 23 out of 277 arriving flights. It said online check-in and the self-bag drop were still available, while check-in at the airport was mainly being done with laptops and iPads.

"It is not clear when we will be able to switch back to the normal check-in and boarding system," a spokesperson for Brussels airport said.

Dublin Airport said some airlines were using manual workarounds to issue bag tags and boarding passes, resulting in longer queues at check-in desks.

Berlin Brandenburg Airport didn't respond to a request for comment.

Shares in European airlines traded lower Monday across the board. International Consolidated Airlines Group--which brings together British Airways and Iberia among others--fell 1.4% in midday trading in Europe, while Deutsche Lufthansa lost 1.5% and Air France-KLM dropped 1.1%.

Among the low-cost carriers, easyJet lost 1.4%, Wizz Air fell 1.45% and Ryanair was down 1.2%. German travel operator TUI dropped 1.4%.

RTX shares were down 0.7% in U.S. premarket trading.

David Mound, head of research and community at cybersecurity company Shinobi Security, said the attack against Collins Aerospace's systems is a stark reminder that security is only as strong as the most vulnerable vendor in a company's supply chain.

"The aviation industry runs on an intricate web of legacy systems and providers, making it an inevitable target, but inevitability shouldn't mean acceptance," he said.

This is the latest of a series of cyberattacks against Western companies, which is causing concern among business leaders.

British automaker Jaguar Land Rover, owned by India's Tata Motors, and luxury group Kering, the company behind the Gucci and Yves Saint Laurent brands, disclosed cyberattacks this month. JLR stopped production, saying manufacturing and retail operations had been severely disrupted by the cyberattack.

U.K. retailer Marks & Spencer, French luxury brand Louis Vuitton and Australian airline Qantas also reported cyberattacks earlier this year.

Write to Cristina Gallardo at cristina.gallardo@wsj.com

(END) Dow Jones Newswires

September 22, 2025 06:52 ET (10:52 GMT)

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