The National Security Agency (NSA) issued an operational security bulletin in February 2025, warning employees about vulnerabilities in the encrypted messaging application Signal. This alert followed an incident where Defense Secretary Pete Hegseth accidentally shared sensitive war plans in a Signal chat shortly before U.S. military operations in Yemen. The bulletin labeled Signal as a high-value target for interception and highlighted the sophistication of Russian hacking groups using phishing tactics to breach encrypted conversations. NSA personnel were instructed not to share sensitive information via third-party messaging applications and to avoid connections with unknown individuals. National Intelligence Director Tulsi Gabbard and CIA Director John Ratcliffe testified before a Senate panel, affirming that no classified information was exchanged in the chat, but the NSA emphasized that even unclassified information should not be shared on Signal. Ratcliffe defended Signal as an approved communication tool, while both officials denied knowledge of operational details related to the military strike.