CWE-551Incorrect Behavior Order: Authorization Before Parsing and Canonicalization

PUBLISHEDweakness record
released 2006-07-19 · last modified 2025-12-11

Metadata

CWE ID:
CWE-551
Abstraction:
Base
Structure:
Simple
Status:
Incomplete
Release Date:
2006-07-19
Latest Modification Date:
2025-12-11

Weakness Name

Incorrect Behavior Order: Authorization Before Parsing and Canonicalization

Description

If a web server does not fully parse requested URLs before it examines them for authorization, it may be possible for an attacker to bypass authorization protection.

For instance, the character strings /./ and / both mean current directory. If /SomeDirectory is a protected directory and an attacker requests /./SomeDirectory, the attacker may be able to gain access to the resource if /./ is not converted to / before the authorization check is performed.

Common Consequences

Scope:
Access Control
Impact:
Bypass Protection Mechanism

Related Weaknesses