Yahoo News reports:

American officials discovered that the Russians had dramatically improved their ability to decrypt certain types of secure communications and had successfully tracked devices used by elite FBI surveillance teams. Officials also feared that the Russians may have devised other ways to monitor U.S. intelligence communications, including hacking into computers not connected to the internet. Senior FBI and CIA officials briefed congressional leaders on these issues as part of a wide-ranging examination on Capitol Hill of U.S. counterintelligence vulnerabilities.

These compromises, the full gravity of which became clear to U.S. officials in 2012, gave Russian spies in American cities including Washington, New York and San Francisco key insights into the location of undercover FBI surveillance teams, and likely the actual substance of FBI communications, according to former officials. They provided the Russians opportunities to potentially shake off FBI surveillance and communicate with sensitive human sources, check on remote recording devices and even gather intelligence on their FBI pursuers, the former officials said.

“When we found out about this, the light bulb went on — that this could be why we haven’t seen [certain types of] activity” from known Russian spies in the United States, said a former senior intelligence official.

The compromise of FBI systems occurred not long after the White House’s 2010 decision to arrest and expose a group of “illegals” – Russian operatives embedded in American society under deep non-official cover – and reflected a resurgence of Russian espionage. Just a few months after the illegals pleaded guilty in July 2010, the FBI opened a new investigation into a group of New York-based undercover Russian intelligence officers. These Russian spies, the FBI discovered, were attempting to recruit a ring of U.S. assets — including Carter Page, an American businessman who would later act as an unpaid foreign policy adviser to Donald Trump’s 2016 presidential campaign.

The breaches also spoke to larger challenges faced by U.S. intelligence agencies in guarding the nation’s secrets, an issue highlighted by recent revelations, first published by CNN, that the CIA was forced to extract a key Russian asset and bring him to the U.S. in 2017. The asset was reportedly critical to the U.S. intelligence community’s conclusion that Russian President Vladimir Putin had personally directed the interference in the 2016 presidential election in support of Donald Trump.

Yahoo spoke about these previously unreported technical breaches and the larger government debates surrounding U.S. policies toward Russia with more than 50 current and former intelligence and national security officials, most of whom requested anonymity to discuss sensitive operations and internal discussions. While the officials expressed a variety of views on what went wrong with U.S.-Russian relations, some said the United States at times neglected to appreciate the espionage challenge from Moscow, and paid a significant price for a failure to prioritize technical threats. [Continue reading…]