57 lines
2.0 KiB
YAML
57 lines
2.0 KiB
YAML
id: azure-nsg-dns-unrestricted
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info:
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name: Unrestricted DNS Access in Azure NSGs
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author: princechaddha
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severity: high
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description: |
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Ensure that Microsoft Azure network security groups (NSGs) do not allow unrestricted inbound access on TCP and UDP port 53 to prevent DNS amplification attacks and other DNS-related threats.
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impact: |
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Allowing unrestricted access on TCP and UDP port 53 can make DNS servers vulnerable to various types of cyber attacks, disrupting network operations.
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remediation: |
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Restrict access to DNS services by configuring NSG rules to only allow trusted sources and necessary traffic on TCP and UDP port 53.
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reference:
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- https://docs.microsoft.com/en-us/azure/virtual-network/network-security-groups-overview
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tags: cloud,devops,azure,microsoft,nsg,azure-cloud-config
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flow: |
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code(1);
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for (let NsgData of iterate(template.nsgdata)) {
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NsgData = JSON.parse(NsgData)
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set("nsg", NsgData.name)
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set("resourcegroup", NsgData.resourceGroup)
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code(2)
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}
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self-contained: true
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code:
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- engine:
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- sh
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- bash
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source: |
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az network nsg list --query '[*].{name:name, resourceGroup:resourceGroup}' --output json
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extractors:
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- type: json
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name: nsgdata
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internal: true
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json:
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- '.[]'
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- engine:
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- sh
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- bash
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source: |
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az network nsg rule list --nsg-name $nsg --resource-group $resourcegroup --query "[?direction=='Inbound' && access=='Allow' && (protocol=='TCP' || protocol=='UDP') && (destinationPortRange=='53')]"
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matchers:
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- type: word
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words:
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- '"sourceAddressPrefix": "*"'
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- '"sourceAddressPrefix": "internet"'
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- '"sourceAddressPrefix": "any"'
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extractors:
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- type: dsl
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dsl:
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- 'nsg + " has unrestricted access on TCP and UDP port 53"'
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# digest: 4b0a004830460221008b8f04054777f77d5380360bc515531774a4ad7e063edabe1619fd600aad455d0221009a10b51064b5f63c339c89146773b5e3c4fc834fd4fb3d609a3387c38a2b5d2d:922c64590222798bb761d5b6d8e72950 |