1st and the 2nd rounds of interviews are tough. The most difficult questions were about DEP/ASLR. Knowing just the definition is not good enough, you should understand where these concepts are applied and where they can be exploited.
Security Research Interview Questions
46 security research interview questions shared by candidates
What is a hash function
How would you implement a dictionary where you can find a k-letter word in O(k) runtime
How to search all the names that is yours in a file using unix commands
Tell me a little bit about yourself and why you'd be a good fit for this job.
How would you handle a deadline that you know you couldn't meet?
Related to security question it was
How would you go about identifying a string with balanced parentheses.
What is a buffer overflow?
Why do you want to work here?
Viewing 1 - 10 interview questions