Misconfiguration Scanning

Trivy provides built-in policies to detect configuration issues in popular Infrastructure as Code files, such as: Docker, Kubernetes, Terraform, CloudFormation, and more. In addition to built-in policies, you can write your own custom policies, as you can see here.

Quick start

Simply specify a directory containing IaC files such as Terraform, CloudFormation, Azure ARM templates, Helm Charts and Dockerfile.

$ trivy config [YOUR_IaC_DIRECTORY]

Example

$ ls build/
Dockerfile
$ trivy config ./build
2022-05-16T13:29:29.952+0100    INFO    Detected config files: 1

Dockerfile (dockerfile)
=======================
Tests: 23 (SUCCESSES: 22, FAILURES: 1, EXCEPTIONS: 0)
Failures: 1 (UNKNOWN: 0, LOW: 0, MEDIUM: 1, HIGH: 0, CRITICAL: 0)

MEDIUM: Specify a tag in the 'FROM' statement for image 'alpine'
══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════
When using a 'FROM' statement you should use a specific tag to avoid uncontrolled behavior when the image is updated.

See https://avd.aquasec.com/misconfig/ds001
──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
Dockerfile:1
──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
1 [ FROM alpine:latest
──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────

You can also enable misconfiguration detection in container image, filesystem and git repository scanning via --scanners misconfig.

$ trivy image --scanners misconfig IMAGE_NAME

$ trivy fs --scanners misconfig /path/to/dir

Note

Misconfiguration detection is not enabled by default in image, fs and repo subcommands.

Unlike the config subcommand, image, fs and repo subcommands can also scan for vulnerabilities and secrets at the same time. You can specify --scanners vuln,misconfig,secret to enable vulnerability and secret detection as well as misconfiguration detection.

Example

$ ls myapp/
Dockerfile Pipfile.lock
$ trivy fs --scanners vuln,misconfig,secret --severity HIGH,CRITICAL myapp/
2022-05-16T13:42:21.440+0100    INFO    Number of language-specific files: 1
2022-05-16T13:42:21.440+0100    INFO    Detecting pipenv vulnerabilities...
2022-05-16T13:42:21.440+0100    INFO    Detected config files: 1

Pipfile.lock (pipenv)
=====================
Total: 1 (HIGH: 1, CRITICAL: 0)

┌──────────┬────────────────┬──────────┬───────────────────┬───────────────┬───────────────────────────────────────────────────────────┐
│ Library  │ Vulnerability  │ Severity │ Installed Version │ Fixed Version │                           Title                           │
├──────────┼────────────────┼──────────┼───────────────────┼───────────────┼───────────────────────────────────────────────────────────┤
│ httplib2 │ CVE-2021-21240 │ HIGH     │ 0.12.1            │ 0.19.0        │ python-httplib2: Regular expression denial of service via │
│          │                │          │                   │               │ malicious header                                          │
│          │                │          │                   │               │ https://avd.aquasec.com/nvd/cve-2021-21240                │
└──────────┴────────────────┴──────────┴───────────────────┴───────────────┴───────────────────────────────────────────────────────────┘

Dockerfile (dockerfile)
=======================
Tests: 17 (SUCCESSES: 16, FAILURES: 1, EXCEPTIONS: 0)
Failures: 1 (HIGH: 1, CRITICAL: 0)

HIGH: Last USER command in Dockerfile should not be 'root'
════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════
Running containers with 'root' user can lead to a container escape situation. It is a best practice to run containers as non-root users, which can be done by adding a 'USER' statement to the Dockerfile.

See https://avd.aquasec.com/misconfig/ds002
────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
Dockerfile:3
────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
3 [ USER root
────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────

In the above example, Trivy detected vulnerabilities of Python dependencies and misconfigurations in Dockerfile.

Type detection

The specified directory can contain mixed types of IaC files. Trivy automatically detects config types and applies relevant policies.

For example, the following example holds IaC files for Terraform, CloudFormation, Kubernetes, Helm Charts, and Dockerfile in the same directory.

$ ls iac/
Dockerfile  deployment.yaml  main.tf mysql-8.8.26.tar
$ trivy conf --severity HIGH,CRITICAL ./iac

Result

2022-06-06T11:01:21.142+0100    INFO    Detected config files: 8

Dockerfile (dockerfile)

Tests: 21 (SUCCESSES: 20, FAILURES: 1, EXCEPTIONS: 0)
Failures: 1 (MEDIUM: 0, HIGH: 1, CRITICAL: 0)

HIGH: Specify at least 1 USER command in Dockerfile with non-root user as argument
═══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════
Running containers with 'root' user can lead to a container escape situation. It is a best practice to run containers as non-root users, which can be done by adding a 'USER' statement to the Dockerfile.

See https://avd.aquasec.com/misconfig/ds002
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────



deployment.yaml (kubernetes)

Tests: 20 (SUCCESSES: 15, FAILURES: 5, EXCEPTIONS: 0)
Failures: 5 (MEDIUM: 4, HIGH: 1, CRITICAL: 0)

MEDIUM: Container 'hello-kubernetes' of Deployment 'hello-kubernetes' should set 'securityContext.allowPrivilegeEscalation' to false
═══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════
A program inside the container can elevate its own privileges and run as root, which might give the program control over the container and node.

See https://avd.aquasec.com/misconfig/ksv001
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
 deployment.yaml:16-19
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
  16 ┌       - name: hello-kubernetes
  17 │         image: hello-kubernetes:1.5
  18 │         ports:
  19 └         - containerPort: 8080
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────


HIGH: Deployment 'hello-kubernetes' should not specify '/var/run/docker.socker' in 'spec.template.volumes.hostPath.path'
═══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════
Mounting docker.sock from the host can give the container full root access to the host.

See https://avd.aquasec.com/misconfig/ksv006
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
 deployment.yaml:6-29
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
   6 ┌   replicas: 3
   7 │   selector:
   8 │     matchLabels:
   9 │       app: hello-kubernetes
  10 │   template:
  11 │     metadata:
  12 │       labels:
  13 │         app: hello-kubernetes
  14 └     spec:
  ..   
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────


MEDIUM: Container 'hello-kubernetes' of Deployment 'hello-kubernetes' should set 'securityContext.runAsNonRoot' to true
═══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════
'runAsNonRoot' forces the running image to run as a non-root user to ensure least privileges.

See https://avd.aquasec.com/misconfig/ksv012
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
 deployment.yaml:16-19
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
  16 ┌       - name: hello-kubernetes
  17 │         image: hello-kubernetes:1.5
  18 │         ports:
  19 └         - containerPort: 8080
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────


MEDIUM: Deployment 'hello-kubernetes' should not set 'spec.template.volumes.hostPath'
═══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════
HostPath volumes must be forbidden.

See https://avd.aquasec.com/misconfig/ksv023
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
 deployment.yaml:6-29
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
   6 ┌   replicas: 3
   7 │   selector:
   8 │     matchLabels:
   9 │       app: hello-kubernetes
  10 │   template:
  11 │     metadata:
  12 │       labels:
  13 │         app: hello-kubernetes
  14 └     spec:
  ..   
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────


MEDIUM: Deployment 'hello-kubernetes' should set 'securityContext.sysctl' to the allowed values
═══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════
Sysctls can disable security mechanisms or affect all containers on a host, and should be disallowed except for an allowed 'safe' subset. A sysctl is considered safe if it is namespaced in the container or the Pod, and it is isolated from other Pods or processes on the same Node.

See https://avd.aquasec.com/misconfig/ksv026
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
 deployment.yaml:6-29
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
   6 ┌   replicas: 3
   7 │   selector:
   8 │     matchLabels:
   9 │       app: hello-kubernetes
  10 │   template:
  11 │     metadata:
  12 │       labels:
  13 │         app: hello-kubernetes
  14 └     spec:
  ..   
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────



mysql-8.8.26.tar:templates/primary/statefulset.yaml (helm)

Tests: 20 (SUCCESSES: 18, FAILURES: 2, EXCEPTIONS: 0)
Failures: 2 (MEDIUM: 2, HIGH: 0, CRITICAL: 0)

MEDIUM: Container 'mysql' of StatefulSet 'mysql' should set 'securityContext.allowPrivilegeEscalation' to false
═══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════
A program inside the container can elevate its own privileges and run as root, which might give the program control over the container and node.

See https://avd.aquasec.com/misconfig/ksv001
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
 mysql-8.8.26.tar:templates/primary/statefulset.yaml:56-130
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
  56 ┌         - name: mysql
  57 │           image: docker.io/bitnami/mysql:8.0.28-debian-10-r23
  58 │           imagePullPolicy: "IfNotPresent"
  59 │           securityContext:
  60 │             runAsUser: 1001
  61 │           env:
  62 │             - name: BITNAMI_DEBUG
  63 │               value: "false"
  64 └             - name: MYSQL_ROOT_PASSWORD
  ..   
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────


MEDIUM: Container 'mysql' of StatefulSet 'mysql' should set 'securityContext.runAsNonRoot' to true
═══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════
'runAsNonRoot' forces the running image to run as a non-root user to ensure least privileges.

See https://avd.aquasec.com/misconfig/ksv012
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
 mysql-8.8.26.tar:templates/primary/statefulset.yaml:56-130
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
  56 ┌         - name: mysql
  57 │           image: docker.io/bitnami/mysql:8.0.28-debian-10-r23
  58 │           imagePullPolicy: "IfNotPresent"
  59 │           securityContext:
  60 │             runAsUser: 1001
  61 │           env:
  62 │             - name: BITNAMI_DEBUG
  63 │               value: "false"
  64 └             - name: MYSQL_ROOT_PASSWORD
  ..   
───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────

You can see the config type next to each file name.

Example

Dockerfile (dockerfile)
=======================
Tests: 23 (SUCCESSES: 22, FAILURES: 1, EXCEPTIONS: 0)
Failures: 1 (HIGH: 1, CRITICAL: 0)

...

deployment.yaml (kubernetes)
============================
Tests: 28 (SUCCESSES: 15, FAILURES: 13, EXCEPTIONS: 0)
Failures: 13 (MEDIUM: 4, HIGH: 1, CRITICAL: 0)

...

main.tf (terraform)
===================
Tests: 23 (SUCCESSES: 14, FAILURES: 9, EXCEPTIONS: 0)
Failures: 9 (HIGH: 6, CRITICAL: 1)

...

bucket.yaml (cloudformation)
============================
Tests: 9 (SUCCESSES: 3, FAILURES: 6, EXCEPTIONS: 0)
Failures: 6 (UNKNOWN: 0, LOW: 0, MEDIUM: 2, HIGH: 4, CRITICAL: 0)

...

mysql-8.8.26.tar:templates/primary/statefulset.yaml (helm)
==========================================================
Tests: 20 (SUCCESSES: 18, FAILURES: 2, EXCEPTIONS: 0)
Failures: 2 (MEDIUM: 2, HIGH: 0, CRITICAL: 0)

Configuration

This section describes misconfiguration-specific configuration. Other common options are documented here.

Enabling a subset of misconfiguration scanners

It's possible to only enable certain misconfiguration scanners if you prefer. You can do so by passing the --misconfig-scanners option. This flag takes a comma-separated list of configuration scanner types.

trivy config --misconfig-scanners=terraform,dockerfile .

Will only scan for misconfigurations that pertain to Terraform and Dockerfiles.

Passing custom policies

You can pass policy files or directories including your custom policies through --policy option. This can be repeated for specifying multiple files or directories.

cd examplex/misconf/
trivy conf --policy custom-policy/policy --policy combine/policy --policy policy.rego --namespaces user misconf/mixed

For more details, see Custom Policies.

Tip

You also need to specify --namespaces option.

Passing custom data

You can pass directories including your custom data through --data option. This can be repeated for specifying multiple directories.

cd examples/misconf/custom-data
trivy conf --policy ./policy --data ./data --namespaces user ./configs

For more details, see Custom Data.

Passing namespaces

By default, Trivy evaluates policies defined in builtin.*. If you want to evaluate custom policies in other packages, you have to specify package prefixes through --namespaces option. This can be repeated for specifying multiple packages.

trivy conf --policy ./policy --namespaces main --namespaces user ./configs

Private terraform registries

Trivy can download terraform code from private registries. To pass credentials you must use the TF_TOKEN_ environment variables. You cannot use a .terraformrc or terraform.rc file, these are not supported by trivy yet.

From the terraform docs:

Environment variable names should have the prefix TF_TOKEN_ added to the domain name, with periods encoded as underscores. For example, the value of a variable named TF_TOKEN_app_terraform_io will be used as a bearer authorization token when the CLI makes service requests to the hostname app.terraform.io.

You must convert domain names containing non-ASCII characters to their punycode equivalent with an ACE prefix. For example, token credentials for 例えば.com must be set in a variable called TF_TOKEN_xn--r8j3dr99h_com.

Hyphens are also valid within host names but usually invalid as variable names and may be encoded as double underscores. For example, you can set a token for the domain name café.fr as TF_TOKEN_xn--caf-dma_fr or TF_TOKEN_xn_cafdmafr.

If multiple variables evaluate to the same hostname, Trivy will choose the environment variable name where the dashes have not been encoded as double underscores.

Skipping resources by inline comments

Trivy supports ignoring misconfigured resources by inline comments for Terraform configuration files only.

In cases where Trivy can detect comments of a specific format immediately adjacent to resource definitions, it is possible to ignore findings from a single source of resource definition (in contrast to .trivyignore, which has a directory-wide scope on all of the files scanned). The format for these comments is trivy:ignore:<rule> immediately following the format-specific line-comment token.

The ignore rule must contain one of the possible check IDs that can be found in its metadata: ID, short code or alias. The id from the metadata is not case-sensitive, so you can specify, for example, AVD-AWS-0089 or avd-aws-0089.

For example, to ignore a misconfiguration ID AVD-GCP-0051 in a Terraform HCL file:

#trivy:ignore:AVD-GCP-0051
resource "google_container_cluster" "example" {
  name     = var.cluster_name
  location = var.region
}

You can add multiple ignores on the same comment line:

#trivy:ignore:AVD-GCP-0051 trivy:ignore:AVD-GCP-0053
resource "google_container_cluster" "example" {
  name     = var.cluster_name
  location = var.region
}

You can also specify a long ID, which is formed as follows: <provider>-<service>-<short-code>.

As an example, consider the following check metadata:

# custom:
  # id: AVD-AWS-0089
  # avd_id: AVD-AWS-0089
  # provider: aws
  # service: s3
  # severity: LOW
  # short_code: enable-logging

Long ID would look like the following: aws-s3-enable-logging.

Expiration Date

You can specify the expiration date of the ignore rule in yyyy-mm-dd format. This is a useful feature when you want to make sure that an ignored issue is not forgotten and worth revisiting in the future. For example:

#trivy:ignore:aws-s3-enable-logging:exp:2024-03-10
resource "aws_s3_bucket" "example" {
  bucket = "test"
}

The aws-s3-enable-logging check will be ignored until 2024-03-10 until the ignore rule expires.

Ignoring by attributes

You can ignore a resource by its attribute value. This is useful when using the for-each meta-argument. For example:

locals {
  ports = ["3306", "5432"]
}

#trivy:ignore:aws-ec2-no-public-ingress-sgr[from_port=3306]
resource "aws_security_group_rule" "example" {
  for_each                 = toset(local.ports)
  type                     = "ingress"
  from_port                = each.key
  to_port                  = each.key
  protocol                 = "TCP"
  cidr_blocks              = ["0.0.0.0/0"]
  security_group_id        = aws_security_group.example.id
  source_security_group_id = aws_security_group.example.id
}

The aws-ec2-no-public-ingress-sgr check will be ignored only for the aws_security_group_rule resource with port number 5432. It is important to note that the ignore rule should not enclose the attribute value in quotes, despite the fact that the port is represented as a string.

If you want to ignore multiple resources on different attributes, you can specify multiple ignore rules:

#trivy:ignore:aws-ec2-no-public-ingress-sgr[from_port=3306]
#trivy:ignore:aws-ec2-no-public-ingress-sgr[from_port=5432]

You can also ignore a resource on multiple attributes:

locals {
  rules = {
    first = {
      port = 1000
      type = "ingress"
    },
    second = {
      port = 1000
      type = "egress"
    }
  }
}

#trivy:ignore:aws-ec2-no-public-ingress-sgr[from_port=1000,type=egress]
resource "aws_security_group_rule" "example" {
  for_each = { for k, v in local.rules : k => v }

  type                     = each.value.type
  from_port                = each.value.port
  to_port                  = each.value.port
  protocol                 = "TCP"
  cidr_blocks              = ["0.0.0.0/0"]
  security_group_id        = aws_security_group.example.id
  source_security_group_id = aws_security_group.example.id
}

Note

Currently nested attributes are not supported. For example you will not be able to reference the each.key attribute.

Ignoring module issues

Issues in third-party modules cannot be ignored using the method described above, because you may not have access to modify the module source code. In such a situation you can add ignore rules above the module block, for example:

#trivy:ignore:aws-s3-enable-logging
module "s3_bucket" {
  source = "terraform-aws-modules/s3-bucket/aws"

  bucket = "my-s3-bucket"
}

An example of ignoring checks for a specific bucket in a module:

locals {
  bucket = ["test1", "test2"]
}

#trivy:ignore:*[bucket=test1]
module "s3_bucket" {
  for_each = toset(local.bucket)
  source   = "terraform-aws-modules/s3-bucket/aws"
  bucket   = each.value
}