• Attackers stole IEH employee credentials via a fake Microsoft login page
• Inbox access exposed sensitive defense‑related communications and technical documentation
• Malicious mailbox rules were removed as IEH contained the unauthorized access

Criminals have broken into the email inboxes of IEH Corporation, a significant supplier for the US military and companies in the commercial aerospace and space industry.

In an 8-K report filed with the US Securities and Exchange Commission (SEC), IEH said that unidentified threat actors reached out to one of its employees, pretending to be a “prospective business contact”.

The atatckers shared a link to what appeared to be a Microsoft document, prompting the victim to log in. Obviously, the login page was bogus, and the login credentials were relayed to the attackers instead.

Malicious mailbox rules

“The threat actor gained access to mailbox contents, including email messages, attachments, customer communications, purchase orders, engineering-related documentation, and potentially export-controlled technical information,” the 8-K reads.

The culprits, however, were not named and no threat actors have yet claimed responsibility for the attack.

IEH said it found no evidence that data had been exfiltrated from the compromised inbox. However, its defenders did discover and remove “malicious mailbox rules”. Usually, crooks set up such rules to automatically forward incoming emails to an inbox under their control, while deleting traces of the activity. This would allow them to continue receiving sensitive emails even after the initial compromise was remediated.

The company also said it completed a full audit of the inbox and done “corrective actions to contain any impact of the unauthorized access.”

IEH Corporation produces “specialized products used in military satellites, missiles and fighter jets,” meaning the information found in the inbox could be quite valuable, especially for nation-states such as Russia, China, North Korea, or Iran.

IEH does not publicly name its clients but it does say that its defense applications include Apache AH-64, V-280 Valor and SH-60 Seahawk programs, as well as Patriot, THAAD, AMRAAM and APKWS missile programs. It reported a revenue of almost $30 million for the 2026 fiscal year.

Via The Record