midWeb Security
What is insecure direct object reference (IDOR)?
Updated May 6, 2026
Short answer
IDOR occurs when users can access unauthorized objects via predictable IDs.
Deep explanation
Lack of access control allows attackers to modify object identifiers and access others' data.
Real-world example
Viewing another user's invoice.
Common mistakes
- Relying only on frontend restrictions.
Follow-up questions
- How to fix IDOR?
- Why is it common?