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🛡️ Azure Storage Account Default Network Access Rule is not set to Deny🟢

Stats​

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Logic​

Similar Policies​

Similar Internal Rules​

RulePoliciesFlags
✉️ dec-x-d127f4072

Description​

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Description​

Restricting default network access provides an additional layer of security, since storage accounts accept connections from clients on any network. To limit access to selected networks, the default action must be changed.

Rationale​

NOTE: This recommendation is only applicable if Public Network Access has not been disabled due to necessity or exception.

Storage accounts should be configured to deny access to traffic from all networks (including internet traffic). Access can be granted to traffic from specific Azure Virtual networks, allowing a secure network boundary for specific applications to be built. Access can also be granted to public internet IP address ranges to enable connections from specific internet or on-premises clients. When network rules are configured, only applications from allowed networks can access a storage account. When calling from an allowed network, applications continue to require proper authorization (a valid access key or SAS token) to access the storage account.

Impact​

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Remediation​

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Remediation​

From Azure Portal​

  1. Go to Storage Accounts.
  2. For each storage account, under Security + networking, click Networking.
  3. Click the Firewalls and virtual networks heading.
  4. Set Public network access to Enabled from selected virtual networks and IP addresses.
  5. Add rules to allow traffic from specific networks and IP addresses.
  6. Click Save.

From Azure CLI​

Use the following command to update default-action to Deny:

az storage account update \
    --name {{storage-account-name}} \
    --resource-group {{resource-group-name}} \
    --default-action Deny

policy.yaml​

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Linked Framework Sections​

SectionSub SectionsInternal RulesPoliciesFlagsCompliance
💼 APRA CPG 234 → 💼 36d access management controls —only authorised users, software and hardware are able to access information assets (refer to Attachment B for further guidance);4161no data
💼 APRA CPG 234 → 💼 36e hardware and software asset controls —appropriate authorisation to prevent security compromises from unauthorised hardware and software assets;4464no data
💼 APRA CPG 234 → 💼 36f network design — to ensure authorised network traffic flows and to reduce the impact of security compromises;76107no data
💼 APRA CPG 234 → 💼 45 An understanding of plausible worst case scenarios can help regulated entities identify and implement additional controls to prevent or reduce the impact of such scenarios. One example is malware that infects computers and encrypts data, both on the infected computer and any connected storage, including (corporate) networks and cloud storage. Such attacks reinforce the importance of protecting the backup environment in the event that the production environment is compromised. Common techniques to achieve this include network segmentation, highly restricted and segregated access controls and network traffic flow restrictions.83115no data
💼 APRA CPG 234 → 💼 52d appropriate segmentation of data, based on sensitivity and access needs;2634no data
💼 APRA CPG 234 → 💼 53 Wholesale access to sensitive data (e.g. contents of customer databases or intellectual property that can be exploited for personal gain) would be highly restricted to reduce the risk exposure to significant data leakage events. Industry experience of actual data leakage incidents include the unauthorised extraction of debit/credit card details, theft of personally identifiable information, loss of unencrypted backup media and the sale/trade or exploitation of customer identity data.2634no data
💼 CIS Azure v5.0.0 → 💼 9.3.2.3 Ensure default network access rule for storage accounts is set to deny (Automated)1no data
💼 CIS Azure v6.0.0 → 💼 9.3.2.3 Ensure Default Network Access Rule for Storage Accounts is Set to Deny (Automated)1no data
💼 Cloudaware Framework → 💼 Network Exposure137no data
💼 FedRAMP High Security Controls → 💼 AC-4(21) Physical or Logical Separation of Information Flows (M)(H)18141no data
💼 FedRAMP Moderate Security Controls → 💼 AC-4(21) Physical or Logical Separation of Information Flows (M)(H)141no data
💼 NIST SP 800-53 Revision 5 → 💼 AC-4(21) Information Flow Enforcement _ Physical or Logical Separation of Information Flows83141no data
💼 UK Cyber Essentials → 💼 1.2 Prevent access to the administrative interface from the internet85119no data