Question

using the tcp/ip model, explain common network vulnerabilities that exist and common network serivices and applications

Answer 1

Missing data encryption during the communication in LAN network and data sharing also OS command injection &
SQL injection are also possible if data is not encrypted by any of the algorithm.

Buffer overflow is also a big headache in any of the application as its obvious attack that each one has some own limit and beyond that anything can break down.

Missing authentication for critical function like weak username password during user authentication or not properly applied properly or some backdoor even entering right credentials.

Unrestricted upload of dangerous file types like some php file uploading function which can allowed any file could be do more damage.

Cross-site scripting and forgery is web vulnerability that can be applied over http protocol and cookie and session attack is possible on LAN sites.

Download of codes without integrity checks like no antivirus software is installed and no security patches applied.

Use of broken algorithms like some outdated algorigthms which are not updated with latest fixes.

below are also the vulnerabilities

URL redirection to untrusted sites
Path traversal
Bugs
Weak passwords
Software that is already infected with virus

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