Cross-Origin Resource Sharing (CORS) should not allow all domains to access your Function app. Allow only required domains to interact with your Function app.
The following 26 compliance controls are associated with this Policy definition 'Function apps should not have CORS configured to allow every resource to access your apps' (0820b7b9-23aa-4725-a1ce-ae4558f718e5)
Deploy Azure Web Application Firewall (WAF) in front of critical web applications for additional inspection of incoming traffic. Enable Diagnostic Setting for WAF and ingest logs into a Storage Account, Event Hub, or Log Analytics Workspace.
How to deploy Azure WAF:
https://docs.microsoft.com/azure/web-application-firewall/ag/create-waf-policy-ag
Use Azure Security Center to monitor your configuration baseline and use Azure Policy [deny] and [deploy if not exist] rule to enforce secure configuration across Azure compute resources, including VMs, containers, and others.
Understand Azure Policy effects: https://docs.microsoft.com/azure/governance/policy/concepts/effects
Create and manage policies to enforce compliance: https://docs.microsoft.com/azure/governance/policy/tutorials/create-and-manage
**Security Principle:**
Continuously monitor and alert when there is a deviation from the defined configuration baseline. Enforce the desired configuration according to the baseline configuration by denying the non-compliant configuration or deploy a configuration.
**Azure Guidance:**
Use Microsoft Defender for Cloud to configure Azure Policy to audit and enforce configurations of your Azure resources. Use Azure Monitor to create alerts when there is a configuration deviation detected on the resources.
Use Azure Policy [deny] and [deploy if not exist] rule to enforce secure configuration across Azure resources.
For resource configuration audit and enforcement not supported by Azure Policy, you may need to write your own scripts or use third-party tooling to implement the configuration audit and enforcement.
**Implementation and additional context:**
Understand Azure Policy effects:
https://docs.microsoft.com/azure/governance/policy/concepts/effects
Create and manage policies to enforce compliance:
https://docs.microsoft.com/azure/governance/policy/tutorials/create-and-manage
Get compliance data of Azure resources:
https://docs.microsoft.com/azure/governance/policy/how-to/get-compliance-data
Limit information system access to authorized users, processes acting on behalf of authorized users, and devices (including other information systems).
Shared
Microsoft and the customer share responsibilities for implementing this requirement.
Access control policies (e.g., identity- or role-based policies, control matrices, and cryptography) control access between active entities or subjects (i.e., users or processes acting on behalf of users) and passive entities or objects (e.g., devices, files, records, and domains) in systems. Access enforcement mechanisms can be employed at the application and service level to provide increased information security. Other systems include systems internal and external to the organization. This requirement focuses on account management for systems and applications. The definition of and enforcement of access authorizations, other than those determined by account type (e.g., privileged verses non-privileged) are addressed in requirement AC.1.002.
Limit information system access to the types of transactions and functions that authorized users are permitted to execute.
Shared
Microsoft and the customer share responsibilities for implementing this requirement.
Organizations may choose to define access privileges or other attributes by account, by type of account, or a combination of both. System account types include individual, shared, group, system, anonymous, guest, emergency, developer, manufacturer, vendor, and temporary. Other attributes required for authorizing access include restrictions on time-of-day, day-of-week, and point-oforigin. In defining other account attributes, organizations consider system-related requirements (e.g., system upgrades scheduled maintenance,) and mission or business requirements, (e.g., time zone differences, customer requirements, remote access to support travel requirements).
Control the flow of CUI in accordance with approved authorizations.
Shared
Microsoft and the customer share responsibilities for implementing this requirement.
Information flow control regulates where information can travel within a system and between systems (versus who can access the information) and without explicit regard to subsequent accesses to that information. Flow control restrictions include the following: keeping exportcontrolled information from being transmitted in the clear to the Internet; blocking outside traffic that claims to be from within the organization; restricting requests to the Internet that are not from the internal web proxy server; and limiting information transfers between organizations based on data structures and content.
Organizations commonly use information flow control policies and enforcement mechanisms to control the flow of information between designated sources and destinations (e.g., networks, individuals, and devices) within systems and between interconnected systems. Flow control is based on characteristics of the information or the information path. Enforcement occurs in boundary protection devices (e.g., gateways, routers, guards, encrypted tunnels, firewalls) that employ rule sets or establish configuration settings that restrict system services, provide a packetfiltering capability based on header information, or message-filtering capability based on message content (e.g., implementing key word searches or using document characteristics). Organizations also consider the trustworthiness of filtering and inspection mechanisms (i.e., hardware, firmware, and software components) that are critical to information flow enforcement.
Transferring information between systems representing different security domains with different security policies introduces risk that such transfers violate one or more domain security policies. In such situations, information owners or stewards provide guidance at designated policy enforcement points between interconnected systems. Organizations consider mandating specific architectural solutions when required to enforce specific security policies. Enforcement includes: prohibiting information transfers between interconnected systems (i.e., allowing access only); employing hardware mechanisms to enforce one-way information flows; and implementing trustworthy regrading mechanisms to reassign security attributes and security labels.
Restrict, disable, or prevent the use of nonessential programs, functions, ports, protocols, and services.
Shared
Microsoft and the customer share responsibilities for implementing this requirement.
Restricting the use of nonessential software (programs) includes restricting the roles allowed to approve program execution; prohibiting auto-execute; program blacklisting and whitelisting; or restricting the number of program instances executed at the same time. The organization makes a security-based determination which functions, ports, protocols, and/or services are restricted. Bluetooth, File Transfer Protocol (FTP), and peer-to-peer networking are examples of protocols organizations consider preventing the use of, restricting, or disabling.
Deny network communications traffic by default and allow network communications traffic by exception (i.e., deny all, permit by exception).
Shared
Microsoft and the customer share responsibilities for implementing this requirement.
This requirement applies to inbound and outbound network communications traffic at the system boundary and at identified points within the system. A deny-all, permit-by-exception network communications traffic policy ensures that only those connections which are essential and approved are allowed.
The organization:
a. Establishes and documents configuration settings for information technology products employed within the information system using [Assignment: organization-defined security configuration checklists] that reflect the most restrictive mode consistent with operational requirements;
b. Implements the configuration settings;
c. Identifies, documents, and approves any deviations from established configuration settings for [Assignment: organization-defined information system components] based on [Assignment: organization-defined operational requirements]; and
d. Monitors and controls changes to the configuration settings in accordance with organizational policies and procedures.
Supplemental Guidance: Configuration settings are the set of parameters that can be changed in hardware, software, or firmware components of the information system that affect the security posture and/or functionality of the system. Information technology products for which security- related configuration settings can be defined include, for example, mainframe computers, servers (e.g., database, electronic mail, authentication, web, proxy, file, domain name), workstations, input/output devices (e.g., scanners, copiers, and printers), network components (e.g., firewalls, routers, gateways, voice and data switches, wireless access points, network appliances, sensors), operating systems, middleware, and applications. Security-related parameters are those parameters impacting the security state of information systems including the parameters required to satisfy other security control requirements. Security-related parameters include, for example: (i) registry settings; (ii) account, file, directory permission settings; and (iii) settings for functions, ports, protocols, services, and remote connections. Organizations establish organization-wide configuration settings and subsequently derive specific settings for information systems. The established settings become part of the systems configuration baseline.
Common secure configurations (also referred to as security configuration checklists, lockdown
and hardening guides, security reference guides, security technical implementation guides) provide recognized, standardized, and established benchmarks that stipulate secure configuration settings for specific information technology platforms/products and instructions for configuring those information system components to meet operational requirements. Common secure configurations can be developed by a variety of organizations including, for example, information technology product developers, manufacturers, vendors, consortia, academia, industry, federal agencies, and other organizations in the public and private sectors. Common secure configurations include the United States Government Configuration Baseline (USGCB) which affects the implementation of CM-6 and other controls such as AC-19 and CM-7. The Security Content Automation Protocol (SCAP) and the defined standards within the protocol (e.g., Common Configuration Enumeration) provide an effective method to uniquely identify, track, and control configuration settings. OMB establishes federal policy on configuration requirements for federal information systems. Related controls: AC-19, CM-2, CM-3, CM-7, SI-4.
References: OMB Memoranda 07-11, 07-18, 08-22; NIST Special Publications 800-70, 800-128; Web: http://nvd.nist.gov, http://checklists.nist.gov, http://www.nsa.gov.
The organization:
a. Establishes and documents configuration settings for information technology products employed within the information system using [Assignment: organization-defined security configuration checklists] that reflect the most restrictive mode consistent with operational requirements;
b. Implements the configuration settings;
c. Identifies, documents, and approves any deviations from established configuration settings for [Assignment: organization-defined information system components] based on [Assignment: organization-defined operational requirements]; and
d. Monitors and controls changes to the configuration settings in accordance with organizational policies and procedures.
Supplemental Guidance: Configuration settings are the set of parameters that can be changed in hardware, software, or firmware components of the information system that affect the security posture and/or functionality of the system. Information technology products for which security- related configuration settings can be defined include, for example, mainframe computers, servers (e.g., database, electronic mail, authentication, web, proxy, file, domain name), workstations, input/output devices (e.g., scanners, copiers, and printers), network components (e.g., firewalls, routers, gateways, voice and data switches, wireless access points, network appliances, sensors), operating systems, middleware, and applications. Security-related parameters are those parameters impacting the security state of information systems including the parameters required to satisfy other security control requirements. Security-related parameters include, for example: (i) registry settings; (ii) account, file, directory permission settings; and (iii) settings for functions, ports, protocols, services, and remote connections. Organizations establish organization-wide configuration settings and subsequently derive specific settings for information systems. The established settings become part of the systems configuration baseline.
Common secure configurations (also referred to as security configuration checklists, lockdown
and hardening guides, security reference guides, security technical implementation guides) provide recognized, standardized, and established benchmarks that stipulate secure configuration settings for specific information technology platforms/products and instructions for configuring those information system components to meet operational requirements. Common secure configurations can be developed by a variety of organizations including, for example, information technology product developers, manufacturers, vendors, consortia, academia, industry, federal agencies, and other organizations in the public and private sectors. Common secure configurations include the United States Government Configuration Baseline (USGCB) which affects the implementation of CM-6 and other controls such as AC-19 and CM-7. The Security Content Automation Protocol (SCAP) and the defined standards within the protocol (e.g., Common Configuration Enumeration) provide an effective method to uniquely identify, track, and control configuration settings. OMB establishes federal policy on configuration requirements for federal information systems. Related controls: AC-19, CM-2, CM-3, CM-7, SI-4.
References: OMB Memoranda 07-11, 07-18, 08-22; NIST Special Publications 800-70, 800-128; Web: http://nvd.nist.gov, http://checklists.nist.gov, http://www.nsa.gov.
0902.09s2Organizational.13-09.s 09.08 Exchange of Information
Shared
n/a
Remote (external) access to the organization's information assets and access to external information assets (for which the organization has no control) is based on clearly defined terms and conditions.
0960.09sCSPOrganizational.1-09.s 09.08 Exchange of Information
Shared
n/a
Cloud service providers use secure (e.g., non-clear text and authenticated) standardized network protocols for the import and export of data and to manage the service, and make available a document to consumers (tenants) detailing the relevant interoperability and portability standards that are involved.
Establish and maintain baseline configurations and inventories of organizational systems (including hardware, software, firmware, and documentation) throughout the respective system development life cycles.
Shared
Microsoft and the customer share responsibilities for implementing this requirement.
Baseline configurations are documented, formally reviewed, and agreed-upon specifications for systems or configuration items within those systems. Baseline configurations serve as a basis for future builds, releases, and changes to systems. Baseline configurations include information about system components (e.g., standard software packages installed on workstations, notebook computers, servers, network components, or mobile devices; current version numbers and update and patch information on operating systems and applications; and configuration settings and parameters), network topology, and the logical placement of those components within the system architecture. Baseline configurations of systems also reflect the current enterprise architecture. Maintaining effective baseline configurations requires creating new baselines as organizational systems change over time. Baseline configuration maintenance includes reviewing and updating the baseline configuration when changes are made based on security risks and deviations from the established baseline configuration. Organizations can implement centralized system component inventories that include components from multiple organizational systems. In such situations, organizations ensure that the resulting inventories include system-specific information required for proper component accountability (e.g., system association, system owner). Information deemed necessary for effective accountability of system components includes hardware inventory specifications, software license information, software version numbers, component owners, and for networked components or devices, machine names and network addresses. Inventory specifications include manufacturer, device type, model, serial number, and physical location. [SP 800-128] provides guidance on security-focused configuration management.
Establish and enforce security configuration settings for information technology products employed in organizational systems.
Shared
Microsoft and the customer share responsibilities for implementing this requirement.
Configuration settings are the set of parameters that can be changed in hardware, software, or firmware components of the system that affect the security posture or functionality of the system. Information technology products for which security-related configuration settings can be defined include mainframe computers, servers, workstations, input and output devices (e.g., scanners, copiers, and printers), network components (e.g., firewalls, routers, gateways, voice and data switches, wireless access points, network appliances, sensors), operating systems, middleware, and applications. Security parameters are those parameters impacting the security state of systems including the parameters required to satisfy other security requirements. Security parameters include: registry settings; account, file, directory permission settings; and settings for functions, ports, protocols, and remote connections. Organizations establish organization-wide configuration settings and subsequently derive specific configuration settings for systems. The established settings become part of the systems configuration baseline. Common secure configurations (also referred to as security configuration checklists, lockdown and hardening guides, security reference guides, security technical implementation guides) provide recognized, standardized, and established benchmarks that stipulate secure configuration settings for specific information technology platforms/products and instructions for configuring those system components to meet operational requirements. Common secure configurations can be developed by a variety of organizations including information technology product developers, manufacturers, vendors, consortia, academia, industry, federal agencies, and other organizations in the public and private sectors. [SP 800-70] and [SP 800-128] provide guidance on security configuration settings.
The organization:
a. Establishes and documents configuration settings for information technology products employed within the information system using [Assignment: organization-defined security configuration checklists] that reflect the most restrictive mode consistent with operational requirements;
b. Implements the configuration settings;
c. Identifies, documents, and approves any deviations from established configuration settings for [Assignment: organization-defined information system components] based on [Assignment: organization-defined operational requirements]; and
d. Monitors and controls changes to the configuration settings in accordance with organizational policies and procedures.
Supplemental Guidance: Configuration settings are the set of parameters that can be changed in hardware, software, or firmware components of the information system that affect the security posture and/or functionality of the system. Information technology products for which security- related configuration settings can be defined include, for example, mainframe computers, servers (e.g., database, electronic mail, authentication, web, proxy, file, domain name), workstations, input/output devices (e.g., scanners, copiers, and printers), network components (e.g., firewalls, routers, gateways, voice and data switches, wireless access points, network appliances, sensors), operating systems, middleware, and applications. Security-related parameters are those parameters impacting the security state of information systems including the parameters required to satisfy other security control requirements. Security-related parameters include, for example: (i) registry settings; (ii) account, file, directory permission settings; and (iii) settings for functions, ports, protocols, services, and remote connections. Organizations establish organization-wide configuration settings and subsequently derive specific settings for information systems. The established settings become part of the systems configuration baseline.
Common secure configurations (also referred to as security configuration checklists, lockdown
and hardening guides, security reference guides, security technical implementation guides) provide recognized, standardized, and established benchmarks that stipulate secure configuration settings for specific information technology platforms/products and instructions for configuring those information system components to meet operational requirements. Common secure configurations can be developed by a variety of organizations including, for example, information technology product developers, manufacturers, vendors, consortia, academia, industry, federal agencies, and other organizations in the public and private sectors. Common secure configurations include the United States Government Configuration Baseline (USGCB) which affects the implementation of CM-6 and other controls such as AC-19 and CM-7. The Security Content Automation Protocol (SCAP) and the defined standards within the protocol (e.g., Common Configuration Enumeration) provide an effective method to uniquely identify, track, and control configuration settings. OMB establishes federal policy on configuration requirements for federal information systems. Related controls: AC-19, CM-2, CM-3, CM-7, SI-4.
References: OMB Memoranda 07-11, 07-18, 08-22; NIST Special Publications 800-70, 800-128; Web: http://nvd.nist.gov, http://checklists.nist.gov, http://www.nsa.gov.
a. Establish and document configuration settings for components employed within the system that reflect the most restrictive mode consistent with operational requirements using [Assignment: organization-defined common secure configurations];
b. Implement the configuration settings;
c. Identify, document, and approve any deviations from established configuration settings for [Assignment: organization-defined system components] based on [Assignment: organization-defined operational requirements]; and
d. Monitor and control changes to the configuration settings in accordance with organizational policies and procedures.
Agencies SHOULD follow the documentation provided in the Open Web Application Security Project guide to building secure Web applications and Web services.
The Open Web Application Security Project guide provides a comprehensive resource to consult when developing Web applications.
Ensure overall network security controls are implemented including the following:
(a) dedicated firewalls at all segments. All external-facing firewalls must be deployed on High Availability (HA) configuration and “fail-close” mode activated. Deploy different brand name/model for two firewalls located in sequence within the same network path;
(b) IPS at all critical network segments with the capability to inspect and monitor encrypted network traffic;
(c) web and email filtering systems such as web-proxy, spam filter and anti-spoofing controls;
(d) endpoint protection solution to detect and remove security threats including viruses and malicious software;
(e) solution to mitigate advanced persistent threats including zero-day and signatureless malware; and
(f) capture the full network packets to rebuild relevant network sessions to aid forensics in the event of incidents.
Prevent or detect against unauthorized or malicious software
Shared
The customer is responsible for implementing this recommendation.
Restricts Application and Software Installation — The ability to install applications
and software is restricted to authorized individuals.
• Detects Unauthorized Changes to Software and Configuration Parameters — Processes are in place to detect changes to software and configuration parameters that
may be indicative of unauthorized or malicious software.
• Uses a Defined Change Control Process — A management-defined change control
process is used for the implementation of software.
• Uses Antivirus and Anti-Malware Software — Antivirus and anti-malware software
is implemented and maintained to provide for the interception or detection and remediation of malware.
• Scans Information Assets from Outside the Entity for Malware and Other Unauthorized Software — Procedures are in place to scan information assets that have been
transferred or returned to the entity’s custody for malware and other unauthorized
software and to remove any items detected prior to its implementation on the network.
The customer is responsible for implementing this recommendation.
Manages Changes Throughout the System Life Cycle — A process for managing
system changes throughout the life cycle of the system and its components (infrastructure, data, software, and procedures) is used to support system availability and
processing integrity.
• Authorizes Changes — A process is in place to authorize system changes prior to
development.
• Designs and Develops Changes — A process is in place to design and develop system changes.
• Documents Changes — A process is in place to document system changes to support ongoing maintenance of the system and to support system users in performing
their responsibilities.
• Tracks System Changes — A process is in place to track system changes prior to
implementation.
• Configures Software — A process is in place to select and implement the configuration parameters used to control the functionality of software.
• Tests System Changes — A process is in place to test system changes prior to implementation.
• Approves System Changes — A process is in place to approve system changes prior
to implementation.
• Deploys System Changes — A process is in place to implement system changes.
• Identifies and Evaluates System Changes — Objectives affected by system changes
are identified and the ability of the modified system to meet the objectives is evaluated throughout the system development life cycle.
• Identifies Changes in Infrastructure, Data, Software, and Procedures Required to
Remediate Incidents — Changes in infrastructure, data, software, and procedures
required to remediate incidents to continue to meet objectives are identified and the
change process is initiated upon identification.
• Creates Baseline Configuration of IT Technology — A baseline configuration of IT
and control systems is created and maintained.
• Provides for Changes Necessary in Emergency Situations — A process is in place
for authorizing, designing, testing, approving, and implementing changes necessary
in emergency situations (that is, changes that need to be implemented in an urgent
time frame).
Additional points of focus that apply only in an engagement using the trust services criteria for
confidentiality:
• Protects Confidential Information — The entity protects confidential information
during system design, development, testing, implementation, and change processes
to meet the entity’s objectives related to confidentiality.
Additional points of focus that apply only in an engagement using the trust services criteria for
privacy:
• Protects Personal Information — The entity protects personal information during
system design, development, testing, implementation, and change processes to meet
the entity’s objectives related to privacy.