Microsoft Defender for Containers alternatives for Kubernetes vulnerability scanning
Teams looking beyond Defender for Containers usually run clusters outside Azure, dislike a bill that grows with every node, or want a scanner and scoring they can audit rather than a cloud provider’s black box.
Facts last checked . Prices and features change — verify with the vendor before deciding.
What Microsoft Defender for Containers does well
Before the list: Microsoft Defender for Containers is a good tool for the right team. Microsoft Defender for Containers is the container-security plan in Defender for Cloud: agentless vulnerability assessment of AKS, EKS, GKE and Arc-connected clusters, registry scanning and an optional runtime sensor, priced per vCore.
- The only large incumbent with published pricing: about $7 per vCore per month, with registry scans included.
- Native for Azure shops: integrated into the portal, Defender CSPM and Microsoft Sentinel.
- Agentless assessment plus an optional sensor for runtime detection.
- Queryable SBOMs and “exploitability insights” on findings.
Microsoft Defender for Containers pricing
Microsoft publishes Defender for Containers at roughly $7 per vCore per month, including 20 registry scans per vCore with an overage of about $0.29 per image digest. Cost scales with the compute in your clusters. StackRadar prices per cluster: five clusters on Pro cost $59 per month whether they have 12 vCores or 1,200.
Microsoft Defender for Containers alternatives
1. StackRadar (that's us)
StackRadar keeps a CycloneDX SBOM for every image running in your Kubernetes clusters and re-checks it against OSV.dev advisories as they land — no rescan. Findings are ranked by the Radar Score, which combines CVSS, EPSS and the CISA KEV catalogue in a published formula, and every finding carries its workload, Helm release and ArgoCD application. One dashboard covers every cluster, with 30 days to two years of history by plan. The scanner installs as one Helm chart, its source is published, releases are signed, and data stays in the EU. Free for one cluster; Pro $59 per month; Business $199 per month.
Where Microsoft Defender for Containers is stronger: you are an Azure-centric organisation already in Defender for Cloud and Sentinel. See StackRadar vs Microsoft Defender for Containers for the full comparison.
2. Wiz
Wiz is the category-defining agentless cloud security platform — a security graph that correlates vulnerabilities with exposure, identities and attack paths across cloud accounts and Kubernetes — acquired by Google in 2026.
Best for: You need cloud-wide posture, identity and attack-path analysis, not just Kubernetes vulnerabilities. Pricing: Enterprise; ~$24K/yr per 100 workloads on marketplaces. Compare with StackRadar · Wiz website
3. Sysdig Secure
Sysdig Secure is an enterprise cloud-native application protection platform built on Falco, with an eBPF agent per node, runtime threat detection, and vulnerability management that pairs SBOMs with runtime “in use” data.
Best for: You need runtime threat detection and response, not just vulnerability tracking. Pricing: Quote-only; reported ~$40–120 per host per month. Compare with StackRadar · Sysdig Secure website
4. Trivy Operator
Trivy Operator is the free, Apache-2.0 Kubernetes operator from Aqua Security that scans running workloads with Trivy and writes the results into the cluster as custom resources.
Best for: You run one or two clusters and mainly want to know what is vulnerable right now. Pricing: Free (Apache-2.0); you run and operate it. Compare with StackRadar · Trivy Operator website
Should you switch?
Choose Microsoft Defender for Containers if
- You are an Azure-centric organisation already in Defender for Cloud and Sentinel.
- You want runtime detection and posture from the same vendor as your cloud.
- Your clusters are small enough that per-vCore pricing is cheap.
Choose StackRadar if
- You run clusters outside Azure or outside the big three clouds entirely.
- You want a flat per-cluster price that does not grow with node count.
- You want an auditable scanner, open advisory data and EU-only residency.
Frequently asked questions
How much does Defender for Containers cost?
About $7 per vCore per month, published by Microsoft, with registry scanning included up to 20 scans per vCore. A 12-vCore cluster is roughly $82 per month; cost grows with cluster size.
Does Defender for Containers work outside Azure?
Yes, for EKS, GKE and Arc-enabled clusters, though the experience is centred on the Azure portal and Defender for Cloud.