Week 7 - Web Security Threats Flashcards
What is Cross Site Scripting (XSS)
XSS is when the attacker embeds malicious client-side scripts into a legitimate website
Where does XSS happen?
when a website does not sanitize user input.
what are the two XSS categories?
Stored XSS attack and
Reflected XSS attack
what is Stored XSS attack?
attacker injects malicious script into a webpage, then stores it into it’s database.
victim requests data from the database but receives the compromised data
How does a stored XSS attack work on vulnerable websites?
the website must have an area of user input that is stored in a database and can be retrieved by the victim without being processed.
e.g a comment section
What are potential consequences of a stored XSS attack?
the attacker can redirect the victim to another website where malicious actions like:
phishing, malware downloads, accessing session cookies, or redirecting users to harmful websites.
<script> window.open(‘http://unsafewebsite.html’) </script>
What is a reflected XSS attack?
Malicious script is stored in the URL and the server reflects this back to the user’s browser.
How can an attacker deliver a reflected XSS payload to the victim?
an attacker might send a malicious URL via email or via forums, using URL shorteners to disguise the script
How to mitigate XSS attacks?
- don’t allow untrusted data to be inserted into sensitive areas
- use proper encoding (HTML encoding) for all user input to ensure it cannot be executed as script.
What is broken Authentication?
when an attacker is able to compromise passwords, session keys or user account information to assume the user’s identity
How does Broken Authentication happen?
when people choose their own password or session management. it is risky because it makes the system prone to vulnerabilities
What is Sensitive Data Exposure?
when sensitive information (passwords, credit card details etc) are exposed or compromised due to security flaws (poor encryption or lack of access control)
How does Sensitive Data Exposure happen?
through SQL injection attacks or compromises of databases or other services
How can you mitigate sensitive data exposure?
- do not store unnecessary sensitive information
- use appropriate access and authentication controls
- encrypt sensitive data
What are XML External Entities (XXE) vulnerabilites?
when XML processes in a website are provided with malicious external data. This data could be a virus or a form of malware
