North Korean hackers are exploiting an email security flaw in attacks used to gather sensitive intelligence and information, a new U.S. cybersecurity advisory warned.

The NSA and FBI warned that the APT43 North Korea-linked hacking group exploits weak email Domain-based Message Authentication Reporting and Conformance (DMARC) policies to mask spearphishing attacks.

The Kimsuky hacking group is exploiting improper configurations of an email protection feature known as DMARC, US agencies say.

In a concerted effort to thwart a pernicious email hacking scheme orchestrated by North Korean operatives, American officials are raising the alarm and urging institutions to fortify their cyber defenses.