The U.S. government, through a joint bulletin by the National Security Agency (NSA), the Federal Bureau of Investigation (FBI), and the Department of State, has issued a new cybersecurity advisory warning about North Korean threat actors. These actors have been engaging in sophisticated email spoofing campaigns designed to appear as if they are sent from legitimate and trusted sources. This form of spear-phishing is utilized by North Korean operatives to collect valuable intelligence on geopolitical events, adversary foreign policies, and any information that could impact the interests of the Democratic People’s Republic of Korea (DPRK).
The advisory highlights that these North Korean actors, specifically a group known as Kimsuky, exploit vulnerabilities in DNS DMARC record policies to conceal their social engineering attempts. Kimsuky, which is associated with other North Korean hacking entities like the Lazarus Group, uses this strategy to send spoofed emails that mimic credible domains, thereby gaining illicit access to the private documents, research, and communications of their targets. This approach has been observed in their recent campaigns targeting foreign policy experts, discussing critical topics such as nuclear disarmament and U.S.-South Korea policies.
Proofpoint, a security firm, reported that Kimsuky began incorporating this method into their operations in December 2023 as part of a broader effort to influence and gather data from foreign policy experts. The group is described as “savvy social engineering experts” who engage their targets over extended periods through benign conversations to build trust. They use various aliases, impersonating DPRK subject matter experts across think tanks, academia, journalism, and independent research, often inviting targets to share insights via email or formal documents.
To mitigate these threats, the U.S. government recommends organizations update their DMARC policies. These updates would direct email servers to treat messages failing DMARC checks as suspicious or spam and generate aggregate feedback reports. This strategy is intended to enhance defenses against such phishing attacks, ensuring that emails from unverified sources are adequately scrutinized and prevented from reaching their intended targets. This guidance aims to curb the effectiveness of North Korean cyber espionage activities by improving organizational email security protocols.
