The Statement of Applicability (SoA) is an important component of the ISO 27001 information security management system (ISMS) standard.
What is the Statement of Applicability (SoA)
It is a document that outlines the scope of the ISMS and identifies the applicable security controls to the organization’s information assets.
Statement of Applicability (SoA) purpose
SoA’s purpose is to provide a comprehensive overview of the organization’s information security posture and help the organization manage and improve security practices.
The SoA is typically created during the implementation phase of an ISO 27001 project, and it is based on the results of the risk assessment and risk treatment processes.
Risk Assessment and Risk Treatment
The risk assessment process involves identifying the organization’s information assets, evaluating the threats and vulnerabilities that could impact those assets, and assessing the potential impact of those threats on the organization’s business operations.
The risk treatment process involves selecting and implementing appropriate security controls to mitigate the identified risks.
Statement of Applicability (SoA) Creation
Once the risk assessment and risk treatment processes have been completed, the organization can create its SoA.
The Statement of Applicability (SoA) should identify the security controls that have been implemented, and it should explain how those controls address the organization’s specific risks and requirements.
The Statement should also provide evidence that the controls have been implemented and that they are operating effectively.
The SoA is an important document because it helps the organization communicate its security posture to stakeholders. Stakeholders include customers, partners, and regulators.
It also helps the organization to identify any gaps or weaknesses in its security posture. The SoA prioritizes improvements to its security practices.
What is included in a Statement of Applicability (SoA):
The SoA typically includes the following sections:
- Introduction: This section provides an overview of the organization and its information security objectives.
- Scope: This section defines the boundaries of the ISMS and identifies the assets that are covered by the ISMS.
- Security controls: This section identifies the security controls that have been implemented and explains how they address the organization’s risks and requirements.
- The controls are typically organized according to the ISO 27001 Annex A framework. The Annex provides a comprehensive list of security controls that can be used to address different types of risks.
- Justification for exclusions: This section explains why certain security controls have not been implemented. It also provides evidence that the risks associated with those controls have been assessed and accepted by the organization.
- Compliance status: This section provides evidence that the organization is complying with relevant laws, regulations, and contractual requirements.
- Review and approval: This section identifies the individuals who have reviewed and approved the SoA.
SoA Security Control Generic Example:
An example of a security control that might be included in an SoA is access control.
Access control is a security control that is designed to ensure that only authorized individuals have access to an organization’s information assets.
Access control can be implemented in a variety of ways, such as through the use of passwords, biometric authentication, or smart cards.
The SoA would identify the specific access control measures that have been implemented and would explain how those measures address the organization’s specific risks and requirements.
In conclusion, the Statement of Applicability is a critical component of the ISO 27001 standard. It provides a comprehensive overview of an organization’s information security posture.
It helps the organization identify and address security risks, and it provides evidence to stakeholders that the organization is taking appropriate measures to protect its information assets.
By following the ISO 27001 standard and creating a robust SoA, organizations can enhance their security practices and demonstrate their commitment to protecting sensitive information.
Example of a Statement of Applicability (SoA) on an e-commerce company:
Let’s consider a hypothetical e-commerce company that is implementing an ISMS based on the ISO 27001 standard.
Identified Risks:
During the risk assessment process, the organization identified a risk related to the availability of its website. Specifically, the organization determined that a DDoS (Distributed Denial of Service) attack could potentially cause the website to become unavailable to customers.
To mitigate this risk, the organization decided to implement network security controls, such as firewalls and intrusion prevention systems (IPS), to prevent and detect DDoS attacks.
The organization then created its Statement of Applicability, which identified the specific security controls that had been implemented to address the identified risks.
Security Controls:
In the section on network security, the SoA listed the following security controls:
- Firewall: The organization has implemented firewalls to monitor and control the traffic that flows in and out of its network. The firewall is configured to block traffic that is associated with known DDoS attack sources.
- Intrusion Prevention System (IPS): The organization has implemented an IPS to detect and prevent DDoS attacks. The IPS uses advanced algorithms to analyze traffic patterns and identify potential DDoS attacks. If an attack is detected, the IPS will automatically block traffic from the attacking IP addresses.
The SoA also explained how these security controls addressed the organization’s specific risks and requirements.
Further examples:
For example, the SoA noted that the firewall helps to prevent DDoS attacks by blocking traffic from known attack sources.
The SoA also noted that the IPS helps to detect and prevent DDoS attacks by analyzing traffic patterns and blocking traffic from attacking IP addresses.
By creating a comprehensive SoA that clearly identifies the security controls that have been implemented, the organization can demonstrate to its stakeholders that it has taken appropriate measures to protect its systems and ensure the availability of its website.
Example of a Statement of Applicability (SoA) in a financial services organization:
During the risk assessment process, a financial services organization identified a risk related to the confidentiality of customer data.
Specifically, the organization determined that unauthorized individuals could potentially gain access to customer data through the use of stolen or compromised passwords.
To mitigate this risk, the organization decided to implement access control measures, such as two-factor authentication and password policies that require complex passwords and regular password changes.
The organization then created its Statement of Applicability, which identified the specific security controls that had been implemented to address the identified risks.
SoA Security Controls:
In the section on access control, the SoA listed the following security controls:
- Two-factor authentication: All employees, contractors, and vendors who need access to customer data are required to use two-factor authentication when logging in to the organization’s systems. This helps to ensure that only authorized individuals have access to sensitive information.
- Password policies: The organization has implemented password policies that require employees, contractors, and vendors to use complex passwords that are at least 12 characters long and that include a mix of upper and lower case letters, numbers, and special characters. Passwords must be changed every 90 days, and employees are prohibited from reusing old passwords.
The SoA also explained how these security controls addressed the organization’s specific risks and requirements.
Examples:
For example, the SoA noted that two-factor authentication reduces the risk of unauthorized access to customer data by requiring an additional factor, such as a fingerprint or a security token, in addition to a password.
The SoA also noted that the password policies help to ensure that passwords are sufficiently complex and that employees are regularly changing their passwords, which reduces the risk of password-based attacks.
Further Security Controls:
In addition to access control, the financial services organization implemented other security controls to address the risks identified during the risk assessment.
These included:
- Encryption: The organization uses encryption to protect sensitive data in transit and at rest. This includes encrypting data that is transmitted over the internet and encrypting data that is stored on the organization’s servers.
- Incident management: The organization has established an incident management process to detect and respond to security incidents. The process includes procedures for reporting incidents, investigating incidents, and implementing corrective actions to prevent similar incidents from occurring in the future.
- Physical security: The organization has implemented physical security measures to protect its facilities and equipment from unauthorized access. This includes using access control systems, surveillance cameras, and security guards to monitor and control access to the organization’s premises.
Additional Features on a Statement of Applicability (SoA):
In addition to creating a comprehensive Statement of Applicability (SoA), the financial services organization should also ensure that it conducts regular security audits to assess the effectiveness of its security controls and identify areas for improvement.
Security Audits
Security audits can be conducted by internal or external auditors and can include a range of assessments, such as vulnerability scans, penetration testing, and compliance audits.
Cryptographic Controls and Encryption
To further strengthen its security posture, the financial services organization should also consider implementing cryptographic controls, which can help to protect the confidentiality, integrity, and authenticity of its data.
Cryptographic controls include encryption, digital signatures, and hash functions, and can be used to protect data both in transit and at rest.
Encryption is particularly important for financial services organizations, which handle sensitive customer data, such as account numbers, social security numbers, and credit card information.
By encrypting this data, the organization can help to ensure that it remains confidential and is not accessed or intercepted by unauthorized individuals.
Digital signatures and hash functions can be used to ensure the integrity and authenticity of data.
For example, digital signatures can be used to sign and verify the authenticity of electronic documents, while cryptographic algorithms and hash functions can be used to create a unique digital fingerprint of a document, making it easy to verify that the document has not been altered.
Conclusion:
In conclusion, the Statement of Applicability is an important document for any organization that is implementing an Information Security Management System (ISMS) based on the ISO 27001 standard.
By clearly identifying the security controls that have been implemented and explaining how they address the organization’s specific risks and requirements, the SoA can help to demonstrate the organization’s commitment to information security and provide a useful reference document for employees, contractors, and vendors.
To further strengthen its security posture, the organization should also conduct regular security audits to protect the confidentiality, integrity, and authenticity of its data.
