Register now or log in to join your professional community.
Check out the Open Web Application Security Project (OWASP) and it's regular list of top web vulnerabilities out there. This project regularly maintains this list and descriptions of vulnerability. It also provides some tools to determine vulnerability.
There is also an important topic related to data security that is called Man in Middle. this is used to change request parameters/headers on the fly using differnet http tools
you also must know about
-Encryption
-Decryption
-Man in the Middle Attack
-Guessable Passwords
-Attacks Countermeasures.
Sorry, I'm not professional by Cross-Site Scripting and SQL injection
Cross site scripting and SQL injection are two different animals, however both are software vulnerabilities.
Cross-site scripting (XSS) is a type of computer security vulnerability typically found in web applications. XSS enables attackers to inject client-side script into web pages viewed by other users. A cross-site scripting vulnerability may be used by attackers to bypass access controls such as the same-origin policy.*
SQL Injection: is another form of hacking. You can imagine a logon screen where user needs to type logname and password. Instead of typing longname, hacker types a small snippet of SQL code (language used to manipulate databases such as Oracle, Sybase, MySQL, ...etc.). it depends on how the database and application are designed, this little trick might return hidden data back to hacker.
I have developed a whole project with on/off filtration to stop sql injection. If you need further consultation, please contact me.
___________________(*) From Wiki page
Ex:
Logging and storing keystrokes of user actionsWhen present in the right place, XSS could allow an attacker to capture all keystrokes of a user, effectively allowing him to capture usernames, passwords, etc.
When it comes to security, every day there's something new, SSL, Man Im Middle, linux iptables, psad, vpn,bruteforce attacks, DDOS, digital signing and certificates shoud be well understood
As SQL injection attacks get more and more common, organizations need to understand the risks that come with using simple web form functionality, to administer proper training, and to be prepared to recover from an attack.
Broken Authentication and Session Management:
Application functions related to authentication and session management are often implemented incorrectly, allowing attackers to compromise passwords, keys, or session tokens, or to exploit other implementation flaws to assume other users’ identities (temporarily or permanently).
Broken Access Control:
Restrictions on what authenticated users are allowed to do are not properly enforced. Attackers can exploit these flaws to access unauthorized functionality and/or data, such as access other users' accounts, view sensitive files, modify other users’ data, change access rights, etc.
Sensitive Data Exposure:
Many web applications and APIs do not properly protect sensitive data, such as financial, healthcare, and PII. Attackers may steal or modify such weakly protected data to conduct credit card fraud, identity theft, or other crimes. Sensitive data deserves extra protection such as encryption at rest or in transit, as well as special precautions when exchanged with the browser.
for more details visit: OWASP top 10
One should know about clickjacking and CSRF attacks too.
Application should be protected from clickjacking attacks, where an attacker can bring a transparent ui element like form infront of a real UI interface and can make you submit your information to his intended server address.
Understand to protect agains CSRF attacks is also equally important, where an attacker can predict your post action or what data your action will modify on the server.
One should also know about Transport layer security and cryptography
