Is this SQL injection point still exploitable?
– Information Security Stack Exchange No single quotes is allowed, Is this SQL Injection point still exploitable? The id variable comes directly from the GET parameter named id. And the Java web app explicitly disallowed single quote. If a single quote was found in that parameter, the server stop processing it immediately and returns an error.
Which is an example of a SQL injection attack?
In this series, we will be showing step-by-step examples of common attacks. We will start off with a basic SQL Injection attack directed at a web application and leading to privilege escalation to OS root.
Is there a way to block SQL injection?
There was no WAF ( Web Application Firewall) in place to detect the SQL Injection exploitation. A WAF could block the attack even if the application is vulnerable. There was no Intrusion Detection or Intrusion Prevention system in place. Many such systems keep a database with hashes of all the monitored files.
How to protect against SQL injection by escaping single quote?
If you want to blacklist, go right ahead. Quote escaping is good, but within context of the other mitigations. Call parameterized queries only. Better yet, use Stored Procedures exclusively. Avoid using dynamic SQL, and dont use string concatenation to build queries.
How to mitigate SQL injection with digits only?
Check out the Wikipedia article about SQL Injection Mitigation. Assuming that GET parameter ‘id’ in digits-only, the best thing to do is to check if ID really contains digits only, by for example converting it into an INT (and catch the exception if any), and not some nasty things like quotes/slashes/encoded chars/etc.
Can a single quote be used in a SQL filter?
For example, some SQL filters replace all single quotes with a pair of single quotes. However, feeding them an input containing \\’ can bypass this. Also, there is Unicode smuggling, where you use a Unicode character that Java (PHP/Ruby/Python/whatever) understands as being different from a quote, but the database doesn’t.
How to bypass single quotes in PostgreSQL environment?
With postgresql and tomcat environment. You may want to take a look at this paper ( wayback machine link ). It details some methods of bypassing such filters. For example, some SQL filters replace all single quotes with a pair of single quotes. However, feeding them an input containing \\’ can bypass this.