CS 325: Software Engineering

April 14, 2015

Software Security• Security Requirements• Software Security in the Life Cycle

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Security RequirementsAs software becomes more complex and data becomes more sensitive, software systems must meet an increasing number of security requirements.

Identification RequirementsThe system must identify the users or systems with which it is about to interact via passwords, encryption key protocols, etc.

Authentication RequirementsThe system must confirm the identity of the user or system that is trying to

interact with it via biometrics, reverse encryption, etc.Authorization Requirements

The system must determine the extent to which the user or system is authorized to access its information and functionality via access control lists, privilege hierarchies, etc.

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Security RequirementsImmunity RequirementsThe system must protect itself from malicious attacks, such as viruses, worms, and Trojan horses.

Integrity RequirementsThe system must prevent intentional corruption via unauthorized creation,

modification, or deletion of data or files.

Intrusion Detection RequirementsThe system must be able to detect and record any unauthorized attempts to access its files or data.Nonrepudiation

RequirementsThe system must be capable of

preventing anyone who accessed its files or data from denying it later.

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Security Requirements

Privacy RequirementsThe system must protect the privacy rights of its users and of anyone affected by its data and files.

Survivability RequirementsThe system must be able to withstand

the intentional loss or destruction of its constituent files and data.

Resilience RequirementsThe system must be able to recover adequately from any successful attack.

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Software Security in the Life CycleSecurity mechanisms can be put into place at several locations within the software life cycle.

Requirements and

Use Cases Design Test Plans CodeTest

ResultsField

Feedback

Abuse Cases – Similar to use cases, they

describe the

system’s behavior

when it’s

under attack

Security Reqs.

– Specific security needs,

like passwords and encrypt

ion

Risk Analysi

s – Clarify req.

docs. & identify possibl

e attacks

External

Review – Have parties outside

the design team

review the

design for

security issues

Risk-Based Security Tests – Use attack pattern

s & threar models to test system security

Static Analysis Tools –

Scan the source

code for common

vulnerabilities

Penetration Testing – Search

for architectural flaws

in the fielded

environment that wouldn’t appear in

the developm

ent lab

Security Breaks – Have the customer

report post-

delivery security

problems so

preventive

measures can be put in

place in future

releases