COMMON WEAKNESS ENUMERATIONDraft

CWE-784

Reliance on Cookies without Validation and Integrity Checking in a Security Decision

The product uses a protection mechanism that relies on the existence or values of a cookie, but it does not properly ensure that the cookie is valid for the associated user.

Soyutlama

Variant

Yapı

Simple

Sömürü İhtimali

High

Problemi anla

Problem nedir?

The product uses a protection mechanism that relies on the existence or values of a cookie, but it does not properly ensure that the cookie is valid for the associated user.

Genişletilmiş açıklama

Attackers can easily modify cookies, within the browser or by implementing the client-side code outside of the browser. Attackers can bypass protection mechanisms such as authorization and authentication by modifying the cookie to contain an expected value.

Kök neden

Problem nasıl ve ne zaman oluşur?

Yaşam döngüsü evresi

Implementation

Risk

Başarılı sömürü neye yol açar?

Bypass Protection MechanismGain Privileges or Assume Identity

Etkilenen güvenlik alanları: Access Control

It is dangerous to use cookies to set a user's privileges. The cookie can be manipulated to claim a high level of authorization, or to claim that successful authentication has occurred.

Savunma

Nasıl önlenir ve çözülür?

Architecture and Design

Mimari ve tasarım yaklaşımı

Detay
Avoid using cookie data for a security-related decision.

Implementation

Uygulama aşaması savunması

Detay
Perform thorough input validation (i.e.: server side validation) on the cookie data if you're going to use it for a security related decision.

Architecture and Design

Mimari ve tasarım yaklaşımı

Detay
Add integrity checks to detect tampering.

Architecture and Design

Mimari ve tasarım yaklaşımı

Detay
Protect critical cookies from replay attacks, since cross-site scripting or other attacks may allow attackers to steal a strongly-encrypted cookie that also passes integrity checks. This mitigation applies to cookies that should only be valid during a single transaction or session. By enforcing timeouts, you may limit the scope of an attack. As part of your integrity check, use an unpredictable, server-side value that is not exposed to the client.