John Webster Leslie

Web Leslie represents and advises emerging and leading companies on a broad array of technology issues, including on cybersecurity, national security, investigations, and data privacy matters.
Web provides strategic advice and counsel on cybersecurity preparedness, data breach, cross-border privacy law, and government investigations, and helps clients navigate complex policy matters related to cybersecurity and national security.

In addition to his regular practice, Web also counsels pro bono clients on technology, immigration, and criminal law matters, including representing a client sentenced to life without parole by a non-unanimous jury in Louisiana.

Web previously served in government in various roles at the Department of Homeland Security, including at the Cybersecurity and Infrastructure Security Agency (CISA), where he specialized in cybersecurity policy, public-private partnerships, and interagency cyber operations. He also served as Special Assistant to the Secretary of Homeland Security.

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On August 21, 2023, the Cybersecurity and Infrastructure Security Agency (“CISA”), National Security Agency (“NSA”), and National Institute of Standards and Technology (“NIST”) issued a joint quantum-readiness factsheet (the “Factsheet”) to inform organizations—particularly those that support critical infrastructure sectors—about quantum computing threats and to urge these organizations to begin planning for future migration to…

On March 21, 2023, the United States Cybersecurity and Infrastructure Security Agency (“CISA”) announced the issuance of updated Cybersecurity Performance Goals (“CPGs”).  The CPGs, which were originally released in October 2022, are intended to establish a set of fundamental cybersecurity practices to be voluntarily implemented by critical infrastructure owners and operators across all critical infrastructure sectors.  The CPGs apply to both information technology (“IT”) and operational technology (“OT”) and are designed to reduce risk related to known, high-impact cyber threats and adversarial tactics, techniques, and procedures (“TTPs”).…

Continue Reading CISA Releases Revised Cybersecurity Performance Goals for Critical Infrastructure

The Federal Energy Regulatory Commission (“FERC”) issued a final rule (Order No. 887) directing the North American Electric Reliability Corporation (“NERC”) to develop new or modified Reliability Standards that require internal network security monitoring (“INSM”) within Critical Infrastructure Protection (“CIP”) networked environments.  This Order may be of interest to entities that develop, implement, or maintain hardware or software for operational technologies associated with bulk electric systems (“BES”).…

Continue Reading FERC Orders Development of New Internal Network Security Monitoring Standards

On April 20, 2022, the cybersecurity authorities of the United States, Australia, Canada, New Zealand, and the United Kingdom—the so-called “Five Eye” governments—announced the publication of Alert AA22-110A, a Joint Cybersecurity Advisory (the “Advisory”) warning critical infrastructure organizations throughout the world that the Russian invasion of Ukraine could expose them “to increased malicious cyber activity from Russian state-sponsored cyber actors or Russian-aligned cybercrime groups.”  The Advisory is intended to update a January 2022 Joint Cybersecurity Advisory, which provided an overview of Russian state-sponsored cyber operations and tactics, techniques, and procedures (“TTPs”).

In its announcement, the authorities urged critical infrastructure network defenders in particular “to prepare for and mitigate potential cyber threats by hardening their cyber defenses” as recommended in the Advisory.
Continue Reading International Cybersecurity Authorities Issue Joint Advisory on Russian Cyber Threats to Critical Infrastructure

On April 7, 2022, the U.S. Cybersecurity & Infrastructure Security Agency (“CISA”) announced the publication of its Sharing Cyber Event Information Fact Sheet (“Fact Sheet”) intended to provide clear guidance to critical infrastructure owners and operators and government partners on voluntary information sharing about “unusual cyber incidents or activity.”  In its announcement, CISA explained that it will use the information provided to fill “critical information gaps,” deploy resources, analyze trends, issue warnings, and “build a common understanding of how adversaries are targeting U.S. networks and critical infrastructure sectors.”

CISA’s announcement of the Fact Sheet encourages entities to visit its Shields Up website for more information; the Shields Up website was recently updated with guidance in response to the heightened risk of Russian cyber attacks.  The Shields Up website recommends that “all organizations—regardless of size—adopt a heightened posture when it comes to cybersecurity and protecting their most critical assets” and provides detailed guidance that entities can use to protect themselves.
Continue Reading CISA Issues Voluntary Information Sharing Guidance for Critical Infrastructure Owners and Operators and Provides Resources for All

On December 2, 2021, the Transportation Security Administration (“TSA”) announced the issuance of Security Directive 1580-21-01, Enhancing Rail Cybersecurity, and Security Directive 1582-21-01, Enhancing Public Transportation and Passenger Railroad Cybersecurity (the “December Security Directives”), and “additional guidance for voluntary measures to strengthen cybersecurity across the transportation sector in response to the ongoing cybersecurity threat to surface transportation systems and associated infrastructure.”  TSA’s announcement clarifies that these actions are “among several steps DHS is taking to increase the cybersecurity of U.S. critical infrastructure.”

The December Security Directives, which become effective on December 31, 2021, impose significant requirements on owners and operators of “higher-risk freight railroads, passenger rail, and rail transit.”  TSA’s announcement also explained that it has extended certain requirements of the December Security Directives to airport and airline operators and has recommended that “all other lower-risk surface transportation owners and operators voluntarily implement” the requirements of the December Security Directives.
Continue Reading TSA Imposes New Cybersecurity Requirements for Rail and Air Sectors