#iso27002/2022/EN
## 8.26 Application security requirements

| Control type | Information security properties           | Cybersecurity concepts | Operational capabilities                           | Security domains     |
| ------------ | ----------------------------------------- | ---------------------- | -------------------------------------------------- | -------------------- |
| #Preventive  | #Confidentiality #Integrity #Availability | #Protect               | #Application_security #System_and_network_security | #Protection #Defence |

  
#### Control
Information security requirements should be identified, specified and approved when developing or acquiring applications.

#### Purpose
To ensure all information security requirements are identified and addressed when developing or acquiring applications.

#### Guidance

<u>General</u>

Application security requirements should be identified and specified. These requirements are usually determined through a risk assessment. The requirements should be developed with the support of information security specialists.

Application security requirements can cover a wide range of topics, depending on the purpose of the application.

Application security requirements should include, as applicable:

a\) level of trust in identity of entities \[e.g. through authentication (see [[ISO_27002_OT 5.17 Authentication information|5.17]], [[ISO_27002_OT 8.2 Privileged access rights\|8.2]] and [[ISO_27002_OT 8.5 Secure authentication|8.5]])];

b\) identifying the type of information and classification level to be processed by the application;

c\) need for segregation of access and level of access to data and functions in the application;

d\) resilience against malicious attacks or unintentional disruptions \[e.g. protection against buffer overflow or structured query language (SQL) injections\];

e\) legal, statutory and regulatory requirements in the jurisdiction where the transaction is generated, processed, completed or stored;

f\) need for privacy associated with all parties involved;

g\) the protection requirements of any confidential information;

h\) protection of data while being processed, in transit and at rest;

i\) need to securely encrypt communications between all involved parties;

j\) input controls, including integrity checks and input validation;

k\) automated controls (e.g. approval limits or dual approvals);

l\) output controls, also considering who can access outputs and its authorization;

m\) restrictions around content of "free-text" fields, as these can lead to uncontrolled storage of confidential data (e.g. personal data);

n\) requirements derived from the business process, such as transaction logging and monitoring, nonrepudiation requirements;

o\) requirements mandated by other security controls (e.g. interfaces to logging and monitoring or data leakage detection systems); 

p) error message handling.

<u>Transactional services</u>

Additionally, for applications offering transactional services between the organization and a partner, the following should be considered when identifying information security requirements:

a\) the level of trust each party requires in each other’s claimed identity;

b\) the level of trust required in the integrity of information exchanged or processed and the mechanisms for identification of lack of integrity (e.g. cyclic redundancy check, hashing, digital signatures);

c\) authorization processes associated with who can approve contents of, issue or sign key transactional documents;

d\) confidentiality, integrity, proof of dispatch and receipt of key documents and the non-repudiation (e.g. contracts associated with tendering and contract processes);

e\) the confidentiality and integrity of any transactions (e.g. orders, delivery address details and confirmation of receipts);

f\) requirements on how long to maintain a transaction confidential;

g\) insurance and other contractual requirements.

<u>Electronic ordering and payment applications</u>

Additionally, for applications involving electronic ordering and payment, the following should be considered:

a\) requirements for maintaining the confidentiality and integrity of order information;

b\) the degree of verification appropriate to verify payment information supplied by a customer;

c\) avoidance of loss or duplication of transaction information;

d\) storing transaction details outside of any publicly accessible environment (e.g. on a storage platform existing on the organizational intranet, and not retained and exposed on electronic storage media directly accessible from the internet);

e\) where a trusted authority is used (e.g. for the purposes of issuing and maintaining digital signatures or digital certificates) security is integrated and embedded throughout the entire end-to-end certificate or signature management process.

Several of the above considerations can be addressed by the application of cryptography (see [[8.24]]), taking into consideration legal requirements (see [[5.31]], [[5.36]], especially see [[5.31]] for cryptography legislation).

**Other information**

Applications accessible via networks are subject to a range of network related threats, such as fraudulent activities, contract disputes or disclosure of information to the public; incomplete transmission, mis- routing, unauthorized message alteration, duplication or replay. Therefore, detailed risk assessments and careful determination of controls are indispensable. Controls required often include cryptographic methods for authentication and securing data transfer.