Key Takeaways
Runtime is the primary attack surface; pre-deployment scans miss active threats after deployment
Misconfigurations, vulnerable images, privilege escalation, and CI/CD injection drive most container breaches
Fidelis Container Secure™ delivers continuous visibility across IaaS, hosts, runtimes, registries, and Kubernetes
Rapid discovery and assessment (under 90 seconds) catch short-lived and rogue containers early
Unauthorized containers are detected and quarantined before lateral movement begins
Host-level monitoring exposes intrusion indicators missed by container-only tools
East-west traffic visibility helps contain attacker movement within clusters
CI/CD integration combined with runtime monitoring reduces risk across the full container lifecycle
Continuous compliance aligns security posture with CIS, PCI, HIPAA, and SOC 2 standards
Container security vulnerabilities in Docker and Kubernetes environments are exploited at runtime, not at the registry gate. Fidelis CloudPassage Halo® Container Secure reduces these risks by providing continuous, automated security monitoring across every layer of the container stack, from IaaS accounts through host systems, container runtimes, image registries, and Kubernetes orchestration.
A registry scan that passed three months ago says nothing about the CVEs weaponized since. A secure deployment policy that was correct at go-live says nothing about the privileged container now running with a mounted Docker socket. Pre-deployment scanning handles what it can see. The runtime is where most container breaches actually happen, and that gap needs dedicated coverage.
That is what Fidelis Container Secure addresses directly. It does not replace image scanning or vulnerability scanners. It covers the ground those tools were never built to reach: what runs, how it behaves, and what happens between pods after any initial access is gained.
59%
of Kubernetes security incidents stem from misconfiguration
87%
of production container images carry critical or high-severity vulnerabilities
60%
of containers live under one minute, too fast for scheduled scans to catch threats
What container security vulnerabilities are attackers actively exploiting in Docker and Kubernetes?
Container image scanning at build time does not catch what changes after deployment. Four attack vectors account for the bulk of common container vulnerabilities exploited in active incidents, and all four operate in the runtime layer where pre-deployment tools have no visibility.
Kubernetes Misconfiguration
RBAC bindings, pod security contexts, network policies, and service account permissions drift over time. Kubernetes does not ship with secure defaults, and Red Hat’s 2024 report puts misconfiguration as the cause of 59% of all Kubernetes security incidents.
Vulnerable Container Images in Production
Images pass pipeline scans at build time and run in production for months. Sysdig’s 2025 report found that 87% of container images in production carry critical or high-severity vulnerabilities. These security flaws accumulate quietly between scan cycles. The scan cleared. The running container is a different question.
Container Escape via Privilege Escalation
Privileged containers, Docker socket mounts, and shared host namespaces collapse container isolation, breaking the security boundary between a workload and its host. Once that boundary is gone, an attacker can execute code at the node level without needing a zero-day. The NSA and CISA Kubernetes Hardening Guide (v1.2) identifies this as a primary attack path requiring continuous scanning and network separation.
CI/CD Pipeline Injection
A tampered or vulnerable image introduced at build time can reach runtime without triggering any alert if no security checks are embedded in the pipeline. This is how supply chain attacks move through containerized environments: quietly, through the tooling teams trust most. Container pipelines are dynamic and ephemeral, which makes them hard for traditional tools to monitor effectively.
None of these four vectors are reliably caught post-deployment by pre-deployment scanning alone. Runtime container security monitoring is the only control layer operating at the actual point of exploitation, after the image is running and before the damage is done.
How does Fidelis Container Secure™ reduce container security vulnerabilities at runtime?
You cannot reduce what you cannot see first
Kubernetes container security monitoring needs a complete, current picture of what is actually running. Fidelis Container Secure automatically discovers and inventories container instances, host systems, image repositories, IaaS accounts, and CaaS environments across AWS, Azure, and GCP. Coverage spans Docker CE, Docker EE, Containerd, and Kubernetes nodes in cloud and on-premises data centers.
Speed is the factor that separates continuous inventory from scheduled scans. Assessments of container hosts and guest instances complete in under 90 seconds. New microagents register on Docker hosts in under 30 seconds. A container that did not exist ten minutes ago is already visible, already evaluated against current security policies. At that pace, rogue workloads get caught during spin-up, not after the cluster is already compromised.
Continuous posture monitoring
Automated CIS compliance checks
Secure cluster configurations
What is running versus what was actually approved?
Rogue containers, those instantiated from unauthorized or unknown images, are one of the clearest indicators of compromise in a containerized environment. Most container security programs have no reliable mechanism to detect them after deployment. Fidelis Container Secure tracks Linux workloads continuously and identifies containers that do not match a recognized image in the current repository. They get classified as rogue and quarantined within seconds, before lateral movement inside the Kubernetes cluster has time to start.
Runtime configuration assessment runs alongside that. Privileged, writable, and interactive containers get flagged at runtime, not just at deployment time. Approved configurations drift. A container that was fine at go-live may now be running with host filesystem access and a mounted Docker socket that nobody has reviewed since initial deployment. Finding it in the live environment is the only way to address it.
The host-level blind spot that container-layer tools miss
Container security monitoring that stops at the workload boundary misses an entire class of threat. Intrusion indicators on Docker hosts and Kubernetes nodes, including log anomalies, file system changes, and unauthorized processes, disappear below the container visibility layer. Fidelis Container Secure monitors at the host level through log analysis, file and system integrity monitoring, and intrusion detection across Docker hosts and Kubernetes nodes simultaneously.
Network traffic, software inventory, configuration security posture, and vulnerability status are tracked as continuous signals, not point-in-time snapshots. File integrity monitoring runs for containers at rest and at runtime, surfacing unexpected modifications whether they originate from malicious code in a tampered image layer, attacker persistence tooling, or an unauthorized process trying to establish a foothold. Kubernetes-native DaemonSet deployment handles microagent distribution automatically across every node. Clusters scale. Coverage follows.
Where lateral movement in a Kubernetes cluster actually hides
Not at the perimeter. Pod-to-pod communication inside a Kubernetes environment bypasses perimeter controls entirely. East-west traffic, the communication happening between containers and pods within the cluster, is the preferred channel for lateral movement after any initial compromise. An attacker in one workload who wants access to a database pod, service account credentials, or the Kubernetes API server does not need to touch anything the perimeter monitors.
Fidelis CloudPassage Halo® Fidelis Container Secure provides network traffic visibility at the container host level and supports host network segmentation to restrict the communication paths available between workloads. When a compromised container reaches toward services it has no reason to contact, that activity surfaces. Segmenting the container host network after any single workload is compromised limits the Kubernetes attack surface and keeps a contained incident from expanding cluster-wide.
Container image security does not stop at the registry scan
Registry connectors scan container images at rest. Pipeline integrations track images in motion. From committed code through image build, registry push, and container spin-up, Fidelis Container Secure evaluates each stage against configured security policies. Alerts fire throughout that process, not only at the initial gate.
Native CI/CD integration with Jenkins, Bamboo, TeamCity, Circle CI, and Travis CI embeds Kubernetes vulnerability scanning directly into the delivery pipeline. Pass/fail build gates stop images carrying known security flaws before they reach runtime. That layer does not replace runtime container security monitoring. It reduces the number of vulnerable images reaching production, which narrows the attack surface before the workload starts.
Full-stack Docker and Kubernetes security coverage across every infrastructure layer
Fidelis Container Secure covers the full container stack from the IaaS account through to the container instance, providing cloud security coverage across every layer that supports containerized workloads. The matrix below maps what Fidelis Container Secure monitors and protects at each layer, sourced directly from the product datasheet and service brief.
Container Stack Coverage: Fidelis CloudPassage Halo Container Secure™
IaaS AccountMonitors IaaS and PaaS accounts to automate security controls for hosts, registry services, IAM, and all resources supporting the containerized environment across AWS, Azure, and GCP.Image RepositoryInventories, evaluates, and assesses image registries and repositories. Identifying vulnerabilities in container images at rest, covering both active and to-be-deployed workloads. Supports Docker Private Registry, Amazon ECR, Azure Container Registry (ACR), Google Container Registry, Docker Hub, and jFrog Artifactory.Host SystemAutomates server instrumentation for discovery and inventory, vulnerability management, system hardening, system integrity monitoring, drift detection, runtime security events, and audit data collection.Container RuntimeCollects configuration and status information for container instances, Kubernetes services, and container runtimes. Evaluates against security policies and compliance controls to detect deviations. Results available via Fidelis Halo GUI or REST API.KubernetesKubernetes-native DaemonSet deployment across every node. Detects rogue containers, privileged configurations, and node intrusions through log monitoring, file and system integrity monitoring, and intrusion detection.DockerDocker host and daemon security monitoring and management. Tracks Docker events, supports container host network segmentation, automates file integrity monitoring for containers at rest and at runtime.
Supported technologies
The following runtimes, infrastructure providers, registries, host operating systems, and CI/CD integrations are supported under a single policy framework and single portal.
Supported Technologies: Fidelis CloudPassage Halo Container Secure™
Container RuntimeDocker CE, Docker EE, ContainerdInfrastructureAWS, Microsoft Azure, Google Cloud Platform, OpenStack, VMware, Rackspace, bare metalImage RegistryDocker Private Registry, Amazon EC2 Container Registry (ECR), Azure Container Registry (ACR), Google Container Registry, Docker Hub, jFrog ArtifactoryContainer Host OSAmazon Linux, Ubuntu, CentOS, RHEL, Debian, CoreOS, Rocky Linux, SUSE Linux, CBL-Mariner LinuxImage Base OSUbuntu, CentOS, RHEL, Debian, Alpine, FedoraCI/CD IntegrationJenkins, Bamboo, TeamCity, Circle CI, Travis CI and moreOther IntegrationsREST API, SIEM (Splunk, SumoLogic), Jira, Slack, ServiceNow
Where Fidelis Container Secure™ fits in the container vulnerability management process
Container vulnerability management has two stages. Pre-deployment scanning covers the build phase. Runtime monitoring covers everything after, across all container environments where workloads are actually running. Most programs invest heavily in the first and leave the second largely uncovered. The comparison below maps which security concerns each stage addresses.
Security ConcernPre-Deployment ScanningFidelis Container Secure™
Known CVEs in images at build timeYESYESKnown CVEs in images at build timeYESYESConfiguration drift post-deploymentNOYESPrivileged container detection at runtimePARTIALYESHost-level intrusion indicatorsNOYESEast-west lateral movement visibilityNOYESFile integrity monitoring at runtimeNOYESCI/CD pipeline security checksYESYESContinuous compliance assessmentNOYESCIS Benchmark and regulatory policy coverageNOYES
Fidelis Container Secure is not a replacement for pre-deployment scanning tools; it works alongside them. It scans container images in the registry before any container is deployed and continues monitoring through the full runtime lifecycle, covering both stages of the container vulnerability management process. Where most scanning tools stop at the build gate, Fidelis Container Secure keeps running: through deployment, into runtime, and across the live cluster. Runtime monitoring is consistently the underinvested half, and Fidelis covers it without dropping registry-level coverage.
Compliance is built in. The policy library covers container security best practices from CIS Benchmarks, PCI, HIPAA, and SysTrust/SOC 2, with Docker and Kubernetes rules maintained by the Fidelis Halo Threat Intelligence team and updated automatically as threats change. Alerts with remediation guidance route to Jira, Slack, and ServiceNow. The bidirectional REST API integrates with existing SIEM and ticketing systems for custom workflows.
What security teams gain from Docker and Kubernetes runtime monitoring
Faster detection of container security vulnerabilities in production
Rogue containers, unauthorized images, privileged configurations, and host-level indicators surface in real time, not on the next scheduled scan.
Reduced attacker dwell time
Continuous runtime monitoring leaves no gaps between scan cycles where threats persist undetected through the workload lifecycle.
Contained lateral movement inside clusters
East-west traffic visibility and host network segmentation restrict the paths available for lateral movement, keeping workload-level breaches workload-level.
Unified incident response across cloud and on-premises
Configuration, alert, and response data from every provider consolidates into the Fidelis Halo portal. One view. No cross-tool correlation.
Continuous compliance posture
Assessment against CIS benchmarks, PCI, HIPAA, and SysTrust/SOC 2 runs continuously. The audit trail reflects actual environment state, not last review state.
Shift-left without leaving runtime exposed
CI/CD integration delivers vulnerability findings to DevOps teams. Container security best practices reach system owners through REST API integrations and message queues.
Shift-Left Ready
Continuous Monitoring
Compliance Controls
Full-stack Security
The runtime gap is where container security breaks down
60% of containers live for under a minute. Attackers have adapted to that. Scheduled scans and perimeter controls are not operating at the same cadence, and the gap between those two rates is where container security vulnerabilities become breaches. Sysdig’s 2026 Cloud-Native Security Report found that over 70% of security teams now rely on runtime-based detections because static controls leave too much container attack surface unaddressed in production.
Fidelis Container Secure operates at the runtime layer. Continuous inventory, rogue container detection, host-level monitoring, east-west traffic visibility, and integrated CI/CD scanning work together to reduce container security vulnerabilities across Docker and Kubernetes environments, cloud and hybrid, at the speed those environments run.
Citations:
The post How Fidelis Container Secure Helps Reduce Container Security Vulnerabilities Across Docker and Kubernetes appeared first on Fidelis Security.
No Responses