Offline, Not Off-Guard: Countering Software Supply Chain Threats in High-Security Environments
By Tom Tapley
4 minute read time
For decades, federal programs operating in high-security or classified domains have relied on air-gapped environments as a primary line of defense. The simple logic being that if networks are physically isolated from the public internet, they can't be attacked from the outside. But, in today's evolving cybersecurity landscape, this assumption of safety through isolation no longer holds.
Nation-state actors are increasingly targeting the software supply chains that support critical federal missions. These sophisticated attacks exploit the trust placed in software updates, build tools, and third-party libraries. Isolation remains a necessary security measure, but it's no longer enough.
In a zero-trust world, security assurance must be continuous, even in disconnected domains. In this blog, we explore how federal environments can counter evolving software supply chain threats and build resilient, verifiable security from the ground up.
The Myth of Safety Through Isolation
Air-gapped networks are only as secure as the software and dependencies that enter them. The belief that physical separation guarantees security creates a false sense of confidence, masking critical vulnerabilities that attackers are eager to exploit. In modern ecosystems, threats extend far beyond what's online. Nation-state adversaries increasingly focus their efforts upstream, embedding malicious code into software supply chains.
A single compromised software update, build tool, or open source library introduced before deployment can cross the air gap and compromise the integrity of the entire environment. These attacks bypass traditional perimeter defenses, because they arrive disguised as trusted components. Compromised software can be introduced into a secure environment through several vectors:
Compromised Updates: Malicious code can be embedded in software updates or patches that are transferred into the air-gapped system. The 2020 SolarWinds attack demonstrated how a trusted software vendor could be used to distribute malware to highly secure networks.
Insider Risk: An employee, whether intentionally malicious or unintentionally negligent, can introduce compromised software via portable media like USB drives.
Pre-Deployment Infiltration: The software supply chain can be infiltrated before a system is ever deployed. If a third-party library or build tool is compromised, the resulting software will be insecure from the start.
Disconnected systems face a paradox: while they are shielded from external networks, they're also cut off from the rapid updates, patches, and visibility that connected systems enjoy. The result is a growing blind spot where outdated components, unverified dependencies, and manual governance processes can accumulate unnoticed. Disconnected environments have to operate under the assumption that compromise is possible. Proactive governance and modern tools are essential for ensuring continuous assurance in these highly sensitive domains.
Building Continuous Assurance in Disconnected Domains
You can't protect what you can't see, and visibility starts with a complete software bill of materials (SBOM). An SBOM provides the transparency needed to understand every dependency, library, and transitive component within an application. Without it, identifying vulnerable or unverified software is nearly impossible, especially when updates occur infrequently.
Pre-vetted component repositories ensure that every artifact entering a classified network is both known and trusted. Federal programs should maintain pre-vetted repositories of open source and third-party components that have been thoroughly scanned, signed, and approved before crossing the air gap. This pre-ingest validation eliminates uncertainty at the source, ensuring that only policy-compliant components ever reach sensitive domains.
Automation plays a critical role in achieving this. Policy-as-code enables agencies to enforce security and compliance requirements automatically, rather than relying solely on human approval chains. Automated workflows can scan components for vulnerabilities, validate signatures, and enforce configuration baselines before ingestion. These measures reduce human error, accelerate authorization, and preserve assurance even in disconnected systems.
This automated "policy-as-code" approach is the engine for a continuous authorization to operate (cATO). It generates a persistent body of evidence (BoE) with every build, including validated SBOMs, that can be provided to an authorizing official (AO). This shifts the process from a slow, static ATO to a live, verifiable one.
Policy-Driven Software Governance for Federal Assurance
Federal mandates increasingly reflect the urgency of securing software supply chains. Executive Order 14028, NIST SP 800-218, and key OMB memoranda like M-22-18 establish clear expectations. For program offices, these aren't just compliance burdens; they are the foundation for building a modern cATO.
Meeting these standards requires more than compliance checklists. Security assurance must begin at the point of acquisition and persist throughout the life cycle of a system. Policy-driven controls ensure that vendors meet federal security expectations before software is ever delivered. These controls also create an enforceable framework that aligns contractors, integrators, and program offices under a shared standard of trust.
Incorporating software governance into acquisition processes also reduces the operational burden on classified operators. By shifting assurance left, well before deployment, agencies can streamline approvals, reduce audit complexity, and enhance confidence in the software they depend on. The long-term benefit is twofold: faster mission readiness and reduced risk exposure across the ecosystem.
By institutionalizing software governance within acquisition and contracting processes, federal organizations can ensure that vendors meet these security requirements before delivery. This shifts assurance left, embedding security into the development life cycle long before deployment and reducing the operational burden on operators in classified environments. Sonatype's platform supports compliance with these key U.S. government requirements, helping organizations build trusted applications.
A New Paradigm for Offline Security
For too long, security in disconnected environments has been based on an outdated assumption of trust. The reality is that security cannot stop at the network boundary. Assurance must be ongoing, verifiable, and automated.
Sonatype's Air-Gapped Environment (SAGE) solution provides the tools needed to secure development ecosystems in both connected and air-gapped environments. By delivering vetted component intelligence and automated governance tools that operate without internet connectivity, we enable federal programs to automate key Risk Management Framework (RMF) controls, maintain compliance, integrity, and speed, without compromising security. This proactive approach empowers organizations to innovate safely, even in the world's most sensitive environments.
Ready to accelerate your path from a static ATO to a live cATO? Request a demo to see how Sonatype can secure your software supply chain.
Tom Tapley specializes in securing software supply chains for Federal environments, bringing deep expertise in aligning agency security, compliance, and operational requirements with modern technology solutions. With a proven track record in supporting mission-critical systems, he bridges the gap ...
Tags
Comply with SBOM Regulations
Meet regulatory requirements with Sonatype SBOM Manager – a single solution for SBOM monitoring, management, and compliance.