Falco

Falco is a free, open-source runtime security project for Linux hosts, containers, Kubernetes and cloud environments. It best suits teams able to run and tune self-hosted security tooling. Its varied event sources are a strong foundation, but useful detection depends on suitable rules and workload-specific performance checks.

Overview

Falco compares events with built-in rules and rules teams create, looking for abnormal behavior, potential threats and compliance violations in real time. That makes it adaptable to different environments, but it is not an automatic catch-all: teams must ensure their rules cover the activity they care about.

Hosted by the CNCF and described as a graduated project, Falco is open source. The core project costs nothing to start; partner offerings for enterprise support and detection rules use custom pricing.

Key features

Broad event inputs

Falco can monitor Linux kernel system calls and ingest Kubernetes audit logs, AWS CloudTrail events, and events from GitHub and Okta. Plugins also cover Docker, AWS EKS audit events and Nomad. This breadth can help teams bring signals from hosts, orchestration and connected services into one detection workflow. The trade-off is that more event sources do not by themselves ensure meaningful coverage; rules must match the events and risks in each environment.

Rule-based detection and response routing

Built-in rules offer a starting point, while custom rules let teams adapt detection to their setup. Falcosidekick can forward events to more than 50 systems, including email, chat, message queues, serverless functions and databases. That flexibility can fit existing response workflows, but teams need to configure both relevant detections and useful destinations.

Kernel monitoring and deployment

Falco uses a modern eBPF driver by default for kernel event monitoring and offers a kernel module for wider compatibility. Installation options cover Linux hosts, Docker containers and Kubernetes, with official Helm charts. This gives infrastructure teams several deployment paths, while keeping operational responsibility with the team running the software.

Falco supports x86_64 and ARM64 architectures; Linux packages are listed for x86_64 and aarch64. Resource use varies with server load and workload, so teams should evaluate performance in the environment where they intend to deploy it.

Pricing

Falco: free. The open-source project has no cost to start, making it suitable for teams that can operate and configure their own runtime monitoring. The free offering does not remove the work of writing appropriate rules or assessing resource use.

Community support is available through Kubernetes Slack and the project's mailing list. Partner-provided enterprise support and detection-rule offerings use custom pricing, which may suit organizations seeking commercial help rather than relying on community channels.

Platforms

Falco runs on Linux and is self-hosted, with deployment options for hosts, Docker containers and Kubernetes. Support for x86_64 and ARM64 widens the range of compatible infrastructure, though the Linux packages are specified for x86_64 and aarch64.

Who it's for

Falco is a strong fit for infrastructure and security teams that want a no-cost, self-hosted way to monitor runtime events across Linux, containers, Kubernetes and selected cloud or service integrations. It is less suitable for teams expecting comprehensive out-of-the-box detection or unwilling to maintain rules and assess workload impact.

Pros and cons

Pros

• Free, open-source core: teams can start without a software charge and adapt rules to their environments.
• Many event sources: kernel syscalls, Kubernetes and cloud audit events, and service integrations can feed detections.
• Flexible deployment and routing: host, Docker and Kubernetes installation options pair with forwarding to more than 50 systems.

Cons

• Coverage requires rule work: Falco does not automatically detect every possible threat.
• Performance needs evaluation: resource use varies with workload and server load.
• Self-hosted operations: teams are responsible for deployment, configuration and ongoing rule suitability.

Alternatives

• Calico Cloud is worth considering for teams seeking a freemium option with web and Windows platforms as well as Linux and self-hosting; its free plan is limited to one user and one cluster, retains logs for 24 hours, and makes the Policy Editor view-only.
• Amazon GuardDuty may suit teams that prefer a paid, pay-as-you-go service with a free trial; charges vary with analyzed volume, data source and AWS Region.
• Qualys TotalCloud offers a free license with limited API calls for control evaluation, alongside a paid cloud platform subscription with custom pricing.
• Tetragon is another free, open-source choice for Linux, Kubernetes and container installations.
• Tracee is a free, Linux-only open-source option that requires a compatible kernel and elevated capabilities.
• Bitdefender Total Security is a paid alternative for Android, iOS, macOS and Windows rather than Falco's Linux and self-hosted platform scope.
• Sysdig Secure is a paid alternative whose licensing is based on the number of hosts in a customer's environment, with compute instances used for CSPM.
• FortiCNAPP is another paid alternative, with Standard tiers offered for one- or three-year terms and entitlement per vCPU.

Explore Cloud Workload Protection Platforms, Kubernetes Security Software and Container Security Software for related categories.

Verdict

Choose Falco if you want a free, flexible runtime monitoring foundation and have the capacity to deploy it, tune rules and check performance against your workloads. Its broad event inputs and forwarding options are compelling for self-hosted infrastructure teams. Look elsewhere if you need detection coverage without ongoing rule work or prefer a commercial service with a different operating model.