U.S. Senator Maria Cantwell is seeking access to network security assessments conducted by Mandiant for AT&T and Verizon following the "Salt Typhoon" cyberattack. Despite assurances from both companies that their networks are secure, they have not released these assessments to the Senate Committee on Commerce, Science and Transportation.
Senator Cantwell expressed her concerns in a letter to Sandra Joyce, Executive Vice President of Mandiant Intelligence and Government Affairs. She noted, “AT&T and Verizon both claimed their networks were secure, but only weeks before the companies made those announcements the U.S. government warned the breach was so significant it made it ‘impossible’ for agencies ‘to predict a time frame on when we’ll have a full eviction.’”
A memo from the Department of Homeland Security revealed that Salt Typhoon had significantly compromised a state’s Army National Guard network last year. On June 12, Senator Cantwell requested documents from AT&T and Verizon CEOs regarding remaining vulnerabilities in their networks due to Salt Typhoon.
“Both AT&T and Verizon confirmed the existence of relevant assessments conducted by Mandiant that are responsive to my letter, but they have thus far refused to make these key reports available without any compelling reason to keep them hidden from Congress,” stated Senator Cantwell.
She has requested that Mandiant provide all related reports by August 6, 2025.
