Software Supply Chain Security Briefs

Brief 1: Sigstore Adoption Momentum and Practical Migration Guidance

Executive takeaway: Open-source projects and enterprises are accelerating Sigstore adoption to provide identity-bound signing without managing long-lived keys. The momentum is driven by improvements in Fulcio OIDC issuance, Rekor transparency logs, and wide ecosystem tooling support. Teams can adopt Sigstore incrementally by layering it onto existing CI pipelines and registries while keeping compliance evidence for auditors.

Current adoption landscape

Ecosystem uptake: Kubernetes, Python’s pip, Homebrew, and multiple Linux distributions have piloted or released Sigstore-backed signing to reduce trust-on-first-use risk. Cloud-native projects increasingly ship cosign-signed container images and attach attestations to OCI registries.
Identity model: Sigstore’s Fulcio issues short-lived X.509 certificates bound to OpenID Connect identities (e.g., GitHub Actions, Google, or corporate IdPs). Certificates are logged to the Rekor transparency ledger, enabling independent verification of who signed what and when.
Toolchain availability: cosign handles container, file, and blob signing; gitsign provides commit signing without PGP keys; the policy-controller and Kubernetes ImagePolicyWebhook integrations enforce signed image admission. Plugins exist for Tekton Chains, GitHub Actions, GitLab CI, and OCI registries like Harbor and Artifactory.
Ecosystem signals: The OpenSSF and CNCF communities regularly include Sigstore in supply-chain hardening playbooks, and multiple cloud providers now pre-install cosign in default build images, signaling vendor confidence and reducing integration friction for enterprises.

Business value and risk reduction

Reduced key management overhead: Ephemeral certificates remove the need to rotate and protect long-lived signing keys while preserving non-repudiation via Rekor’s append-only log.
Auditability: Each signature and attestation is accompanied by a transparency log entry, producing independent, time-stamped evidence. This supports compliance with SOC 2, ISO 27001, and the Executive Order 14028 directives around provenance.
Interoperability: Because Sigstore relies on standard X.509, OIDC, and OCI artifacts, it fits heterogeneous environments and reduces vendor lock-in compared to proprietary signing services.
Community trust: When downstream consumers can verify signatures with public logs, open-source release processes become more transparent, lowering the risk of supply-chain compromise through compromised maintainer keys.

Migration patterns and recommended steps

Start with container images: Use cosign sign --identity-token $ID_TOKEN $IMAGE in CI. Store signatures and attestations in the same OCI registry repository to keep distribution simple.
Adopt provenance attestations: Enable Tekton Chains or GitHub Actions cosign attest to emit SLSA provenance statements (in-toto format) capturing builder identity, inputs, and outputs. Pin digest references in deployment manifests to ensure deterministic rollouts.
Enforce at cluster ingress: Deploy Sigstore’s policy-controller or Kyverno policies to require valid cosign verify checks for all production namespaces. Start in monitor mode to gather data before moving to enforce.
Extend to commits and binaries: Introduce gitsign for developer commits and cosign for file and binary releases. Publish public verification instructions in release notes to improve community trust.
Integrate with secrets policy: Although Sigstore reduces long-lived key exposure, CI identity tokens still need tight scoping and short lifetimes. Align with OIDC audience restrictions and rotate repository secrets.
Educate developers and release managers: Provide short training on how OIDC identities map to Rekor entries, how to read transparency log proofs, and how to debug common verification failures to avoid release friction.

Operational considerations

Availability: Rekor’s public log and Fulcio CA have published SLAs; for high-assurance environments, mirror logs or run private instances to reduce dependency on public infrastructure during outages.
Longevity and revocation: Short-lived certs limit blast radius. Rekor entries are immutable; revocation is handled by recording key compromise events and shifting trust to new identities rather than deleting log records.
Performance: Signing and verification add milliseconds to CI/CD and admission. Batch verification and local signature caching mitigate latency for high-scale deployments.
Multi-cloud alignment: Because OIDC is portable, Sigstore fits multi-cloud footprints; however, teams must ensure each cloud’s OIDC issuer is trusted by Fulcio or configure custom CA roots for private deployments.

Compliance mapping and evidence retention

SOX/SOC 2 alignment: Use Rekor entry IDs and signed provenance as change evidence tied to release tickets. Retain exported checkpoints to prove transparency log inclusion during audits.
FedRAMP and regulated sectors: For environments requiring offline verification, regularly export Rekor checkpoints and store them in GRC-approved evidence repositories. Configure verification to prefer cached checkpoints when public endpoints are unreachable.
Chain-of-custody documentation: Document how OIDC identities are issued, who controls repository permissions, and how Rekor entries are monitored. This narrative often satisfies auditor questions about signer identity assurance and non-repudiation.

Migration pitfalls and mitigation

Identity drift: Mismatched OIDC issuers across staging and production can lead to verification failures. Standardize on a single issuer per environment and codify it in pipeline templates.
Registry layout confusion: If signatures are stored in separate registries, developers may pull unsigned images unknowingly. Prefer colocating signatures with artifacts and enforce cosign verify --certificate-identity checks in deployment tooling.
Token scoping: Overly broad identity tokens can be misused by compromised CI jobs. Use audience and subject claims that narrow usage to the intended repository and workflow.
Rollback readiness: Pre-sign rollback images and keep their verification material locally to avoid deployment freezes during outages.

Metrics and rollout milestones

Percentage of production images signed and verified in admission.
Number of services with provenance attestations meeting SLSA Build L2 or higher.
Mean-time-to-detect unsigned artifacts in deployment pipelines.
Audit findings demonstrating reconstructable build records via Rekor entries.
Number of release managers trained on Sigstore tooling and verification runbooks.

What good looks like in 6–12 months

Every production image has a cosign signature and an attached provenance attestation stored in the registry.
Admission controllers block unsigned or improperly identified images by default.
Rekor logs (public or private) are mirrored, and checkpoints are archived weekly.
Developers use gitsign by default, and release processes publish verification instructions for consumers.

Key takeaways for leadership

Sigstore provides a low-friction path to verifiable builds without owning keys.
Incremental adoption is feasible: begin with signing and verification before full provenance and admission enforcement.
Investment yields measurable compliance and operational risk reductions while keeping developer workflows lightweight.

Brief 2: Understanding SLSA Levels and Achieving Build Integrity Targets

Executive takeaway: The Supply-chain Levels for Software Artifacts (SLSA) framework defines progressive maturity levels for source integrity, build provenance, and trustworthy distribution. Mapping current controls to SLSA clarifies gaps and aligns engineering, security, and compliance on measurable milestones.

SLSA overview

Level 1 (documentation): Build processes are scripted and outputs are registered, but provenance may be ad hoc. Minimal integrity guarantees.
Level 2 (provenance): Builds are automated, and provenance is generated and authenticated (e.g., signed in-toto statements). Source and build integrity rely on secured version control and builder identity.
Level 3 (non-falsifiable provenance): Builds run on isolated, hardened infrastructure with ephemeral workers. Provenance is generated within the trusted build service and signed with service-managed keys to prevent tampering by the project.
Level 4 (reproducible): Two-party reproducible builds or equivalent controls ensure outputs can be independently recreated, closing supply-chain substitution gaps.

Gap assessment methodology

Map controls: Inventory CI/CD components (source control protections, runner isolation, secret management, binary repositories, deployment gates) and map to SLSA requirements.
Evidence gathering: Determine where provenance is produced, who signs it, and where it’s stored (e.g., OCI registry, artifact store). Identify missing attestations for key services.
Risk-ranking gaps: Prioritize controls that prevent tampering (runner isolation, hermetic builds, dependency pinning) and those that improve detectability (provenance, transparency logs).
Dependency hygiene: Evaluate lockfile usage, dependency update cadence, and hash pinning. SLSA emphasizes deterministic inputs; without strict dependency control, provenance offers limited assurance.
Auditability: Ensure logs capture builder identity, timestamps, and artifact digests. Where logs are mutable, add tamper-evident storage or export to transparency services.

Practical pathways to L3 compliance for cloud-native services

Runner isolation: Use ephemeral, non-privileged build runners with no shared workspace; disable inbound network by default, allow egress only to artifact mirrors and package indexes.
Hermetic/parameterized builds: Pin base images and dependencies with digests; remove network fetches during build by vendorizing or using proxy caches with allowlists.
Trusted provenance generation: Configure Tekton Chains, GitHub Actions OIDC plus cosign attest, or GitLab’s pipeline attestations to emit SLSA provenance signed by the CI service identity, not by the repository secrets.
Policy enforcement: Gate deployments on verifying provenance predicates (builder ID, buildType, source repo digest). Admission controllers or deployment orchestrators should reject artifacts lacking required predicates.
Rebuild validations: Periodically rebuild critical releases from tagged source and compare digests to published artifacts. Investigate deviations to uncover non-deterministic steps or potential tampering.

Integrating SLSA with existing governance

Change management: Tie provenance references to change tickets. Require provenance validation as part of CAB approvals for regulated workloads.
Threat modeling: Update STRIDE or ATT&CK-based threat models to include build-system attack vectors (runner breakout, compromised base images, secret exfiltration) and align mitigations with SLSA controls.
Supplier expectations: Include SLSA L2 or L3 provenance requirements in vendor contracts. Validate third-party attestations on intake and store them alongside internal artifacts.

Measuring progress and success criteria

Control coverage: Percent of services producing SLSA Build L3 provenance for release artifacts.
Tamper resistance: Audit reports demonstrating builder isolation (e.g., VM or container sandboxing, no shared volumes, hardened base images) and secrets minimization.
Rebuild fidelity: Periodic reproducibility tests showing deterministic digests for a sample of releases; discrepancies trigger regression hunts.
Policy adherence: Percentage of deployments blocked due to missing or invalid provenance; downward trends over time indicate maturing pipelines.
Dependency discipline: Ratio of releases built with fully pinned dependencies versus floating versions.

Control implementation examples

Source integrity: Enforce signed commits (via gitsign or SSH signing) and branch protection rules. Require two-person review for version bumps and release tagging to reduce the risk of malicious dependency pinning.
Build pipeline hardening: Use infrastructure-as-code to define hardened runner images with minimal packages, kernel lockdown, and auditd enabled. Rotate runners frequently and disable SSH access to prevent lateral movement.
Credential boundaries: Replace long-lived deploy keys with workload identity tokens scoped to specific repositories and environments. Enforce short lifetimes (<=10 minutes) and audience restrictions aligned to each pipeline stage.
Artifact storage: Store build outputs and attestations in append-only buckets or object stores with versioning enabled. Enable WORM retention where required by compliance to ensure build evidence cannot be retroactively modified.

Developer workflow alignment

Templates and golden paths: Provide reusable pipeline templates that default to digest pinning, provenance generation, and policy checks. Embed unit examples so teams can extend without weakening controls.
Local reproducibility: Offer developer make targets or task files that replicate CI build steps locally using the same containerized toolchain, reducing friction when investigating provenance failures.
Documentation: Maintain a SLSA runbook that explains required predicates, sample cosign verify-attestation commands, and common remediation steps for failed checks.

Organizational considerations

Policy as code: Encode SLSA gates in OPA/Conftest or admission controllers to avoid manual exceptions.
Developer enablement: Provide base pipeline templates and dependency pinning guidance to reduce friction.
Third-party suppliers: Require vendors to deliver provenance meeting SLSA L2 or L3 and validate it during intake.
Training: Offer short courses on reading in-toto predicates, interpreting builder IDs, and troubleshooting failed verification to prevent rollout delays.

Case study-style milestones

Quarter 1: Inventory pipelines, enable digest pinning, and produce signed provenance for at least one service per team.
Quarter 2: Move critical services to isolated runners and enforce provenance verification in pre-deploy checks.
Quarter 3: Extend enforcement to production admission, begin reproducibility sampling, and integrate provenance into incident response workflows.

Leadership takeaways

SLSA gives a shared maturity language for engineers and auditors.
Achieving L3 for critical services materially reduces build and release tampering risk.
Progress can be tracked via provenance coverage, dependency pinning rates, and periodic reproducible build drills.

Frequently asked questions for stakeholders

How does SLSA interact with existing DevSecOps controls? SLSA complements SDLC controls by focusing specifically on build integrity and provenance. Policy enforcement can reuse existing OPA or admission pipelines to reduce duplication.
Is SLSA achievable for legacy systems? For platforms without modern CI/CD, start with L1 documentation and L2 provenance from wrapper scripts, then incrementally introduce isolated builders and pinned dependencies. Not all systems will reach L3 immediately, but provenance plus hardened storage still improves assurance.
What is the budget impact? The largest costs come from isolated runners and artifact storage. However, reduced incident response costs and audit efficiency typically offset the infrastructure spend.

Brief 3: Managing Artifact Signing Outages Without Breaking Deployments

Executive takeaway: Dependence on signing services (public CAs, transparency logs, or internal key services) introduces availability risks. Designing resilient verification and deployment workflows prevents outages from halting releases while maintaining integrity guarantees.

Common outage scenarios

Transparency log downtime: Rekor or internal log clusters become unreachable, blocking verification that requires inclusion proofs.
OIDC or CA failures: Fulcio or internal issuance endpoints fail, preventing issuance of short-lived signing certificates.
Key management service (KMS) issues: Hardware security modules or cloud KMS APIs throttle or time out during batch signing.
Dependency registry outages: OCI registries storing signatures/attestations become temporarily unavailable, preventing cosign verify or admission lookups.
Network partitioning: Corporate egress controls or regional outages sever connectivity between build runners and signing infrastructure, producing unsigned artifacts or verification failures.

Resilience strategies

Graceful degradation policies: Configure admission controllers in “warn” or “audit” mode during known outages, but retain logging of unsigned or unverifiable artifacts. Use time-bounded feature flags to automatically revert to enforce once service health restores.
Local verification caches: Mirror signatures, attestations, and Rekor checkpoints to internal caches. Verification can rely on cached checkpoints and inclusion proofs during short outages, with post-facto reconciliation when logs recover.
Redundant authorities: Operate private Fulcio/Rekor instances and periodically mirror entries from public services. Switch verification trust roots via configuration management without altering pipelines.
Fail-secure for high-risk assets: For control-plane components or customer-facing binaries, prefer fail-closed semantics with preapproved rollback bundles that are pre-verified and cached.
Backpressure and retries: Implement exponential backoff and circuit breakers around signing and verification steps in CI/CD to avoid cascading failures during upstream instability.
Workload segregation: Isolate signing infrastructure per business unit to prevent noisy-neighbor effects, but standardize roots of trust to keep verification consistent.

Operational playbook

Health detection: Monitor signing latency, issuance error rates, and verification failures. Expose SLOs for signing services and logs.
Incident response: When verification services degrade, shift admission to audit-only mode using a change ticket and pre-approved runbook. Announce expected blast radius and manual deployment guardrails.
Reconciliation: Once services recover, re-verify artifacts deployed during degraded periods and reissue attestations as needed. Record exception windows for compliance evidence.
Postmortem: Track mean-time-to-recover, number of exceptions granted, and backlog of artifacts needing re-verification.
Chaos testing: Periodically simulate Rekor or CA outages in non-production to validate that caches, feature flags, and rollback bundles work as expected.

Architecture blueprint for high availability

Dual log strategy: Maintain public log trust for openness while running a private, mirrored log for continuity. Verification prefers the private log when public endpoints fail but still records public inclusion proofs when available.
Staged issuance: Use short-lived Fulcio certificates for routine builds and longer-lived emergency certificates stored securely for disaster scenarios where OIDC is unavailable. Guard emergency cert usage with approvals and extensive logging.
Pre-staged attestations: For scheduled maintenance windows, pre-sign critical images and store attestations and signatures in multiple registries and file mirrors to ensure deployments can proceed offline.
Observability: Instrument pipelines to emit metrics on signing attempts, retries, and fallback modes. Alerting should distinguish between signer failures and verification cache hits to avoid false positives.

Metrics and controls

Time spent in audit-only mode vs enforce mode.
Percentage of artifacts with cached verification material enabling offline validation.
Error budget burn rates for signing and log availability SLOs.
Number of deployments executed during degraded verification states and their reconciliation status.
Coverage of chaos tests for signing outage scenarios.

Case walkthrough: transparency log outage

Trigger: Monitoring detects Rekor latency exceeding SLOs and verification failures spike in admission.
Response: Runbook toggles admission to audit-only mode for affected namespaces. Pipelines continue signing but verification leverages cached checkpoints.
Containment: Security team validates that only pre-approved rollouts proceed; high-risk services are paused unless pre-signed rollback bundles exist.
Recovery: When Rekor stabilizes, admission is reverted to enforce. A background job re-verifies artifacts deployed during the outage and records results in an evidence store.
Lessons learned: Identify whether cache warmup, retry policies, or mirrored logs need tuning. Update chaos scenarios to cover any gaps observed during the incident.

Governance considerations

Exception management: All deviations from enforced verification should be time-boxed, ticketed, and approved by the service owner plus security. Automated expirations prevent lingering policy drift.
Separation of duties: Keep signing key custodians and deployment approvers distinct. Even when using OIDC-based signing, ensure RBAC prevents unilateral bypass of verification gates.
Customer assurance: For customer-facing services, publish a brief status note during major signing outages to maintain transparency and document compensating controls.

Readiness checklists

Signing path: Verify that every pipeline has both a primary and fallback signer configuration, plus integration tests that fail if signatures or attestations are missing.
Verification path: Ensure admission or deployment controllers support toggling between enforce and audit modes through change-managed flags.
Cache hygiene: Schedule jobs that refresh Rekor checkpoints and registry mirrors to avoid stale caches causing verification drift.
Playbook drills: Run quarterly tabletop exercises covering CA outages, log unavailability, and registry downtime; record remediation timings.

Tooling landscape

Signing clients: cosign, notation, and platform-native signers (AWS Signer, Azure Sign) can coexist; standardize on verification policies to avoid configuration sprawl.
Policy engines: Use Sigstore policy-controller, Kyverno, or OPA Gatekeeper with custom constraints to express outage behaviors and fallback criteria.
Observability stack: Centralize metrics and logs from Fulcio/Rekor, CI pipelines, and admission controllers to correlate failures quickly.

KPIs for executives

Reduction in deployment delays attributable to signing outages, measured month over month.
Percentage of production services with validated fallback verification paths and documented runbooks.
Median time to reconcile artifacts deployed during degraded verification periods.
Frequency of chaos tests covering signing and verification infrastructure.

Leadership takeaways

Treat signing and transparency as critical infrastructure with explicit SLOs and redundancy.
Design workflows that balance integrity with service availability through controlled, time-bounded exceptions.
Invest in caches and mirrored authorities to keep deployments moving without sacrificing auditability.

Brief 4: Enforcing SBOM Quality and Consumption Across the Lifecycle

Executive takeaway: Software Bills of Materials (SBOMs) are only useful when they are complete, timely, and consumed by downstream tools. Enforcing SBOM generation and validation in CI/CD enables vulnerability management, license compliance, and dependency governance at scale.

SBOM production standards

Formats: Prefer SPDX 2.3 or CycloneDX 1.5 for rich metadata and broad tooling support. Include component versions, licenses, package URLs, cryptographic checksums, and build environment metadata.
Generation points: Produce SBOMs during the build (e.g., syft, cdxgen, bom for Java/Maven, npm ls --json for JavaScript) to avoid drift. For container images, embed SBOMs as OCI artifacts alongside the image and provenance.
Attestation and signing: Sign SBOMs with the same pipeline identity used for artifacts, and store them in OCI or artifact repositories. Link SBOM digests inside provenance attestations for traceability.
Coverage expectations: Every release artifact—including client binaries, server images, and infrastructure charts—should have a corresponding SBOM. Document exceptions with time-bound remediation plans.

Enforcement in CI/CD and deployment

Quality gates: Reject releases lacking SBOMs, missing license fields, or with dependency entries without versions. Use policy-as-code (OPA, Conftest, or in-toto layout verification) to codify checks.
Timeliness: Regenerate SBOMs for rebuilds and patch releases; avoid reusing stale SBOMs when dependencies change via lockfile updates or base image bumps.
Dependency alignment: Validate that SBOM contents align with lockfiles, container layer manifests, and provenance inputs to prevent shadow dependencies.
Downstream consumption: Integrate SBOM ingestion into vulnerability scanners, license compliance tooling, and asset inventories. Surface drift alerts when deployed artifacts lack matching SBOMs.
Admission control: For Kubernetes clusters, require that images present attached SBOM artifacts and verify their signatures during admission. For serverless or VM deployments, integrate SBOM checks into deployment orchestration workflows.

Handling proprietary and third-party software

Supplier requirements: Mandate SPDX or CycloneDX delivery with signed attestations from vendors. Verify signatures and compare SBOM entries against binaries using tools like tern or syft to detect omissions.
Confidential components: For sensitive packages, use redaction-aware formats (e.g., SPDX Lite) while still providing hashes and license identifiers to maintain compliance posture.
License and export controls: Automate detection of restricted licenses and export-controlled components directly from SBOM data before approving intake.

Storage, discovery, and lifecycle management

Registry integration: Store SBOMs as OCI artifacts referenced by image digest. Configure lifecycle policies so SBOMs are retained as long as their corresponding images remain deployable.
Indexing: Maintain an SBOM index service keyed by artifact digest and version. Expose APIs for security scanning, procurement, and incident response teams.
Versioning and diffs: Track SBOM diffs between releases to rapidly identify new components introduced by base image updates or dependency additions.

Metrics and continuous improvement

Percentage of artifacts and images with signed SBOMs attached in the registry.
SBOM freshness (age since build) and alignment rate with deployed digests.
Mean time to remediate high-severity CVEs discovered through SBOM-driven scanning.
Coverage of third-party artifacts with verified SBOMs.
Number of deployment blocks triggered by SBOM quality gates and the median resolution time.

Data quality and completeness guidelines

Checksum coverage: Require checksums for every component entry to enable binary-to-SBOM correlation during forensics. Reject SBOMs with missing hashes or ambiguous component identifiers.
License accuracy: Validate SPDX license IDs and flag NOASSERTION entries for follow-up. Track resolution SLAs so legal approvals do not lag releases.
Build metadata: Capture compiler versions, build arguments, and base image digests to aid reproducibility and vulnerability scoping when toolchain CVEs arise.

Consumption personas and workflows

Security operations: Automate nightly scans that pull SBOMs, compare against vulnerability advisories, and open tickets with affected service owners.
Procurement and legal: Use SBOM indexes to validate license obligations before contract renewals or acquisitions. Export reports demonstrating third-party coverage and compliance posture.
Engineering: Provide dashboards mapping services to SBOM freshness and coverage. Highlight top dependency risk contributors to prioritize refactoring or dependency retirement.

Pitfalls to avoid

Stale SBOM reuse: Copying SBOMs between releases undermines trust; enforce regeneration for each build digest.
Unattested SBOM delivery: SBOMs emailed or shared via unsecured channels cannot be trusted. Always require signed attestations and verify against artifact digests.
Ignoring transitive dependencies: Ensure generation tools capture both direct and transitive components, including OS packages inside containers, to avoid blind spots during vulnerability response.

Operational checkpoints

Pre-release: SBOM generation jobs must pass policy checks and attach signatures before artifacts are promoted to release repositories.
Pre-deployment: Admission or deployment orchestration verifies SBOM signatures and digest alignment; exceptions require security sign-off.
Post-deployment: Observability jobs confirm that running workloads have corresponding SBOMs and provenance in the registry.

Architecture reference

Producers: CI pipelines emit SBOMs, provenance, and signatures and push them to OCI registries.
Index and policy: An internal SBOM index exposes APIs for scanners and policy engines. Admission controllers query both the registry and index before allowing deployments.
Consumers: Vulnerability scanners, asset inventories, and compliance dashboards pull SBOMs and attestations to drive alerts and reporting.

Training and adoption plan

Run short enablement sessions demonstrating SBOM generation for each language ecosystem and how to debug policy failures.
Provide quickstart templates (GitHub Actions, GitLab CI, Jenkins) that wire SBOM generation, signing, and upload by default.
Establish SLAs for SBOM freshness and track them on engineering scorecards to encourage continuous compliance.

Future roadmap items

Evaluate incremental SBOMs for large mono-repos to reduce pipeline cost while preserving completeness.
Integrate runtime package detection (e.g., eBPF-based) to reconcile SBOMs with actual loaded modules for high-sensitivity services.
Align SBOM schemas with vulnerability exploitability metrics (e.g., EPSS, KEV flags) to prioritize remediation workflows.

Incident response and audit readiness

Rapid impact analysis: During a new CVE, query the SBOM index by component name and version to enumerate affected services within minutes. Ensure runbooks reference these queries.
Forensics: Because SBOMs are signed, they provide tamper-evident inventories that can be correlated with provenance to prove what was deployed at a given time.
Audit artifacts: Store signed SBOMs, verification logs, and policy evaluation results in an immutable evidence store to satisfy customer and regulator requests.

Leadership takeaways

SBOMs provide actionable visibility only when enforced as a release prerequisite and actively consumed.
Signing and linking SBOMs to provenance creates verifiable evidence for regulators and customers.
Continuous measurement of SBOM coverage and freshness drives accountability and reduces vulnerability response times.