Pentagon Was Aware Russian Hackers Use Signal App to Spy Days Before SignalGate: Report

The Pentagon sent out an advisory notice warning that Russian hackers were using the messaging app Signal to spy on encrypted conversations—just days after top Trump administration officials accidentally included a journalist in a Signal chat about bombing Houthi sites in Yemen.

The March 18 memo, obtained by NPR, stated, "A vulnerability has been identified in the Signal messenger application" and warned that Russian hacking groups were exploiting its "linked devices" feature to infiltrate private discussions in phishing scams. It also reaffirmed that Signal was not approved for storing or sharing non-public government information.

Despite these warnings, high-ranking officials—including Defense Secretary Pete Hegseth—were using Signal to discuss military operations. The accidental addition of The Atlantic's editor-in-chief Jeffrey Goldberg to the "war plans" chat was made public Monday, igniting controversy over how the administration is handling sensitive information.

John Bolton, former national security adviser under Trump's first administration, blasted the officials' decision. "These are things that are absolutely basic," John Bolton, who served as national security adviser under Trump's first administration, told NPR. "Yet these are cabinet-level people in our government, and yet not one of them ever said, 'Why are we on Signal?'"

The incident, now dubbed SignalGate, has been downplayed by the administration, with Hegseth and national security advisor Mike Waltz attacking Goldberg's credibility and praising the military operation completed under Trump's leadership. Security director Tulsi Gabbard refused to speak about the chat at all, and would not confirm that the text chain's contents were classified.

The revelation of the Pentagon memo implies that the administration is more aware of the chat as a breach in security protocol than they have recognized publicly. Additionally, a 2023 Department of Defense memo had already prohibited using mobile apps for even controlled unclassified information, let alone active military operations.

While Signal has since implemented security upgrades, the revelation that Pentagon officials were using the app despite longstanding warnings has only deepened the controversy.