The Department of Homeland Security is undergoing a significant IT and cybersecurity leadership realignment, including the reported departures of DHS CISO Hemant Baidwan and Deputy CISO Amanda Day. The shakeup follows broader turbulence across DHS and CISA, including the reassignment of acting CISA Director Madhu Gottumukkala to a DHS headquarters role and the resignation of CISA CIO Bob Costello; Day has since moved to the private sector as VP of cybersecurity and trust at Workday.
Separately, President Donald Trump nominated Sen. Markwayne Mullin to lead DHS after firing Secretary Kristi Noem, a move that DHS and CISA personnel described as adding uncertainty to an agency already strained by workforce reductions, leadership instability, and operational impacts from a recent DHS shutdown. While Mullin has supported some cybersecurity-related legislation, employees cited ongoing concerns about CISA’s ability to stabilize without a permanent, Senate-confirmed leader; an unrelated report noted the IRS has launched a “thorough” cybersecurity review amid congressional scrutiny of taxpayer-data sharing and privacy compliance, but that issue is not part of the DHS/CISA leadership event.

Mallory correlates global threat intelligence with your attack surface — know if you’re exposed before adversaries strike.
10 events from the most recent confirmed update back to the earliest known activity.
As part of the realignment, DHS moved to replace Chief Information Security Officer Hemant Baidwan and Deputy CISO Amanda Day, according to sources cited by FedScoop.
DHS launched a significant IT leadership overhaul led in part by CIO Antoine McCord, with plans that sources said could include moving headquarters personnel into component CIO roles and consolidating IT functions under the DHS CIO office.
The Trump administration nominated Sen. Markwayne Mullin to become DHS secretary after Noem's removal, prompting mixed reactions inside DHS and CISA about the department's future direction.
President Trump announced that Homeland Security Secretary Kristi Noem would depart at the end of March, setting off a broader leadership transition across DHS.
FEMA previously dismissed IT personnel and installed Zeke Maldonado as acting FEMA CIO, a move sources said fit a wider DHS effort to consolidate component IT functions under headquarters.
DHS Chief Information Officer Bob Costello resigned as part of broader upheaval in the department's technology leadership ranks.
Former acting CISA Director Madhu Gottumukkala left the role after reported tensions, adding to leadership turnover at the agency.
CISA director nominee Sean Plankey departed an advisory role with the U.S. Coast Guard while his confirmation remained blocked by a Senate hold, prolonging uncertainty over CISA leadership.
A DHS shutdown occurred after fatal shootings by immigration agents in Minneapolis triggered political fallout and a standoff over immigration reforms and DHS funding. The shutdown further destabilized DHS and CISA operations.
Since President Donald Trump returned to office, CISA has operated without a permanent Senate-confirmed director, contributing to prolonged leadership uncertainty at the agency.
Vulnerabilities, threat actors, malware, products, organizations, and breaches Mallory has linked to this story.
2 references tracked. Mallory keeps watching after this page renders.
Map indicators from this story to your assets and identify affected systems in minutes.
Every observed campaign, victim, and pivot linked to actors named in this story.
Malware, exploits, and IOCs connected to the activity described here.
YARA, Sigma, and Snort rules deployed to your SIEM as soon as they’re published.
Get matching new stories delivered to your team as they break — not the next morning.
Ask questions about this story and take action on the answers.