Leader of federal cyber defense programs resigns from CISA - Federal News Network

CYBERSECURITY Leader of federal cyber defense programs resigns from CISA Shelly Hartsook led CISA efforts to improve cybersecurity capacity governmentwide. Her departure continues a steady string of resignations at the cyber agency. Justin Doubleday@jdoubledayWFED March 2, 2026 4:59 pm           The Cybersecurity and Infrastructure Security Agency is losing another key leader who has played a critical role in spearheading governmentwide cyber defenses. Shelly Hartsook, acting associate director in CISA’s cybersecurity division, announced her resignation today, two sources confirmed to Federal News Network. The sources, who requested anonymity because they were not authorized to speak publicly, said Hartsook’s departure was voluntary, though it comes at an uncertain time for the cyber defense agency. One of the sources said Hartsook’s last day at CISA will be March 6. Hartsook did not respond to a request for comment sent to her email or LinkedIn page. CISA did not immediately respond to a request for comment.         Join us June 10 and 11 for Federal News Network's Cloud Exchange where agency and industry leaders will discuss a whole-of-government approach to cloud modernization. Register today! The associate director is a key role within CISA’s cybersecurity division. Mike Duffy previously held that role before he became acting federal chief information security officer at the White House Office of Management and Budget. As the head of the cybersecurity division’s “capacity building” efforts, Hartsook was responsible for managing CISA programs that provide other federal agencies with cybersecurity capabilities, including the Continuous Diagnostics and Mitigation (CDM) program. Hartsook “leads CISA’s efforts to build the capacity of its customers in addressing our nation’s most pressing cybersecurity challenges through the delivery of externally-facing cybersecurity services,” according to a biography posted on the CIO Council’s website. Hartsook first joined CISA in 2020. She had previously spent 15 years in the private sector. During her time at the cyber agency, Hartsook led efforts to “define a long-term strategic recovery roadmap” following the 2020 SolarWinds cyber intrusions, according to the biography. She also spearheaded governmentwide efforts under the May 2021 cybersecurity executive order, including the adoption of “zero trust” architectures and a push to improve the government’s ability to detect cyber threats through improved “logging” practices. Her departure comes after a leadership shakeup and continued personnel turmoil at the U.S. cyber agency. Last week, CISA’s acting director was replaced and moved to another position at the Department of Homeland Security. But not before his reported clashing with CISA’s chief information officer and chief human capital officer led to their respective reassignments.         Sign up for our daily newsletter so you never miss a beat on all things federal Hartsook’s stepping down continues a steady drumbeat of resignations at the cyber agency over the past year. Last month, CISA’s associate director for threat hunting announced he would be leaving for a role in the private sector. CISA has lost roughly one-third of its staff since last January. Many of those departures happened last year under voluntary workforce transition programs as Homeland Security Secretary Kristi Noem and the Trump administration sought to cut CISA’s budget and mission. The workforce cuts and the lack of a Senate-confirmed leader have left the cyber agency adrift over the past year. Copyright © 2026 Federal News Network. All rights reserved. This website is not intended for users located within the European Economic Area.           Justin Doubleday Justin Doubleday covers cybersecurity, homeland security and the intelligence community for Federal News Network. Follow @jdoubledayWFED Sign up for breaking news. Related Stories Getty Images/amgun Federal vulnerability management is stuck. A patch wave is coming anyway. 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