Editing Vulnerability (computer security) (section)

==Vulnerabilities by component==
===Hardware===
{{main |Hardware security bug}} 
Deliberate security bugs can be introduced during or after manufacturing and cause the [[integrated circuit]] not to behave as expected under certain specific circumstances. Testing for security bugs in hardware is quite difficult due to limited time and the complexity of twenty-first century chips,{{sfn|Salmani|2018|p=1}} while the globalization of design and manufacturing has increased the opportunity for these bugs to be introduced by malicious actors.{{sfn|Salmani|2018|p=11}}

===Operating system===
{{see also|Operating system#Security}}
Although [[operating system vulnerabilities]] vary depending on the [[operating system]] in use, a common problem is [[privilege escalation]] bugs that enable the attacker to gain more access than they should be allowed. [[Open-source]] operating systems such as [[Linux]] and [[Android (operating system)|Android]] have a freely accessible [[source code]] and allow anyone to contribute, which could enable the introduction of vulnerabilities. However, the same vulnerabilities also occur in proprietary operating systems such as [[Microsoft Windows]] and [[List of Apple operating systems|Apple operating systems]].{{sfn|Garg|Baliyan|2023|pp=20-25}} All reputable vendors of operating systems provide patches regularly.{{sfn |Sharp|2024|p=271}}

===Client–server applications===
[[Client–server model |Client–server application]]s are downloaded onto the end user's computers and are typically updated less frequently than web applications. Unlike web applications, they interact directly with a user's [[operating system]]. Common vulnerabilities in these applications include:{{sfn |Strout |2023|p=15}}
*Unencrypted data that is in permanent storage or sent over a network is relatively easy for attackers to steal.{{sfn |Strout |2023|p=15}}
*[[Process hijacking]] occurs when an attacker takes over an existing [[computer process]].{{sfn |Strout |2023|p=15}}

===Web applications===
[[Web applications]] run on many websites. Because they are inherently less secure than other applications, they are a leading source of [[data breach]]es and other security incidents.{{sfn |Strout |2023|p=13}}{{sfn|Haber |Hibbert|2018|p=129}} They can include: 
*[[Authentication]] and [[authorization]] failures enable attackers to access data that should be restricted to trusted users.{{sfn |Strout |2023|p=13}}
*[[Business logic vulnerability]] occurs when programmers do not consider unexpected cases arising in [[business logic]].

Attacks used against vulnerabilities in web applications include: 
*[[Cross-site scripting]] (XSS) enables attackers to [[code injection|inject]] and run [[JavaScript]]-based [[malware]] when [[input checking]] is insufficient to reject the injected code.{{sfn |Strout |2023|p=13}} XSS can be persistent, when attackers save the malware in a data field and run it when the data is loaded; it can also be loaded using a malicious [[URL]] link (reflected XSS).{{sfn |Strout |2023|p=13}} Attackers can also insert malicious code into the [[domain object model]].{{sfn |Strout |2023|p=14}}
*[[SQL injection]] and similar attacks manipulate [[database queries]] to gain unauthorized access to data.{{sfn |Strout |2023|p=14}}
*[[Command injection]] is a form of code injection where the attacker places the malware in data fields or [[process]]es. The attacker might be able to take over the entire server.{{sfn |Strout |2023|p=14}}
*[[Cross-site request forgery]] (CSRF) is creating client requests that do malicious actions, such as an attacker changing a user's credentials.{{sfn |Strout |2023|p=14}}
*[[Server-side request forgery]] is similar to CSRF, but the request is forged from the server side and often exploits the enhanced privilege of the server.{{sfn |Strout |2023|p=14}}
*[[Business logic vulnerability]] occurs when programmers do not consider unexpected cases arising in [[business logic]].{{sfn |Strout |2023|pp=14-15}}