New warnings: Russian operatives targeting emails of US nuclear scientists

US officials have recently issued fresh warnings regarding ongoing cyber espionage efforts by Russian operatives, who are actively targeting the email accounts of American nuclear scientists and defense contractors. These warnings, released on Thursday, July 23, 2026, come after private-sector researchers and spy agencies observed a year-long campaign by a group of Russian hackers. Their activities suggest an interest in nuclear fusion technology and intelligence that could potentially benefit Russia's conflict with Ukraine.

The cyberattacks involve sophisticated tactics, including a new "Zero-Click" method that exploits a vulnerability in Zimbra Collaboration Suite (ZCS) software, identified as CVE-2025-66376. This advanced technique allows Russian state-supported hackers, tracked as "Laundry Bear" or TA488, to compromise networks and exfiltrate sensitive data, such as emails, without requiring the user to interact with a malicious link or attachment.

According to US email security firm Proofpoint, which investigated some of these operations, the hackers specifically targeted email servers belonging to nuclear installations and organizations within the defense industrial base in the United States. An advisory from US and allied intelligence agencies has confirmed this as an "ongoing" Russian espionage campaign, noting that similar hacking techniques were first tested in Ukraine before being deployed against NATO member countries.