Incorrect Behavior Order: Authorization Before Parsing and Canonicalization

Opis

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.

Skutki

• Access Control

  Bypass Protection Mechanism

Zapobieganie

• Architecture and Design

  URL Inputs should be decoded and canonicalized to the application's current internal representation before being validated and processed for authorization. Make sure that your application does not decode the same input twice. Such errors could be used to bypass allowlist schemes by introducing dangerous inputs after they have been checked.

Słabość nadrzędna

• CWE-863 Incorrect Authorization
• CWE-696 Incorrect Behavior Order

Pokrewna

• CWE-41 Improper Resolution of Path Equivalence

Kiedy powstaje

• Implementation — REALIZATION: This weakness is caused during implementation of an architectural security tactic.

Dotyczy

Not Language-Specific, Not Technology-Specific, Web Based, Web Server