Japanese electronics manufacturer Japan Aviation Electronics Industry is recovering from a cyberattack for which the Alphv/BlackCat ransomware group has claimed responsibility.

Founded in 1953 and headquartered in Shibuya, Tokyo, Japan Aviation Electronics manufactures electrical connectors, aerospace electronics, and user interface related devices.

The incident, the company said in a notice on its website, occurred on November 2 and involved some of its servers being accessed by an unauthorized external party.

The company said it immediately suspended some of the impacted systems and that it has been assessing the impact of the attack and restoring operations.

The disruption, Japan Aviation Electronics noted, resulted in “some delays in sending and receiving emails”.

“No information leakage has been confirmed to date,” the manufacturing giant also noted.

While Japan Aviation Electronics has not found evidence of data exfiltration, the Alphv/BlackCat ransomware gang claims to have stolen roughly 150,000 documents from the company, including blueprints, contracts, confidential messages, and reports.

Alphv/BlackCat has added Japan Aviation Electronics to its leak website on the Tor network, posting screenshots of documents allegedly stolen from the manufacturer.

The first ransomware family to be written in Rust, Alphv/BlackCat has been active since November 2021, operating under the ransomware-as-a-service (RaaS) business model and likely linked to the Darkside/Blackmatter ransomware gang.

The Alphv/BlackCat group is known for exfiltrating victim data for extortion, deploying file-encrypting ransomware, and engaging various extortion tactics, including distributed denial-of-service (DDoS) attacks, and the harassment of victims’ customers and employees.

In June and May 2023, the gang claimed responsibility for a February 2023 cyberattack against Reddit and for intrusions at Canadian software company Constellation Software and at Western Digital.

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