08What is a TOCTOU race, how does it turn into privilege escalation through files, and how do you write privileged code that avoids it?▼hardNewGoogleMicrosoftApple○ sign inCheck, then use: two system calls, and an attacker in between. The answer interviewers want replaces names with handles and checks with atomic operations, and can show it in code.Open full answer →
24Practical coding: walk a directory tree and find files containing a pattern, safely.▼easyNewGoogleMicrosoftAmazon◆ premiumAn easy coding warm-up with traps a security engineer should spot: symlinks, huge files, unreadable files and paths outside the tree. The scored answer handles each and tests it.Open full answer →