COMMON WEAKNESS ENUMERATIONIncomplete

CWE-827

Improper Control of Document Type Definition

The product does not restrict a reference to a Document Type Definition (DTD) to the intended control sphere. This might allow attackers to reference arbitrary DTDs, possibly causing the product to expose files, consume excessive system resources, or execute arbitrary http requests on behalf of the attacker.

Soyutlama

Variant

Yapı

Simple

Sömürü İhtimali

Medium

Problemi anla

Problem nedir?

The product does not restrict a reference to a Document Type Definition (DTD) to the intended control sphere. This might allow attackers to reference arbitrary DTDs, possibly causing the product to expose files, consume excessive system resources, or execute arbitrary http requests on behalf of the attacker.

Genişletilmiş açıklama

As DTDs are processed, they might try to read or include files on the machine performing the parsing. If an attacker is able to control the DTD, then the attacker might be able to specify sensitive resources or requests or provide malicious content. For example, the SOAP specification prohibits SOAP messages from containing DTDs.

Kök neden

Problem nasıl ve ne zaman oluşur?

Yaşam döngüsü evresi

Implementation

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

Risk

Başarılı sömürü neye yol açar?

Read Files or Directories

Etkilenen güvenlik alanları: Confidentiality

If the attacker is able to include a crafted DTD and a default entity resolver is enabled, the attacker may be able to access arbitrary files on the system.
DoS: Resource Consumption (CPU)DoS: Resource Consumption (Memory)

Etkilenen güvenlik alanları: Availability

The DTD may cause the parser to consume excessive CPU cycles or memory using techniques such as nested or recursive entity references (CWE-776).
Execute Unauthorized Code or CommandsGain Privileges or Assume Identity

Etkilenen güvenlik alanları: Integrity, Confidentiality, Availability, Access Control

The DTD may include arbitrary HTTP requests that the server may execute. This could lead to other attacks leveraging the server's trust relationship with other entities.

Savunma

Nasıl önlenir ve çözülür?

  • Follow secure coding guidelines for input handling and boundary checking.
  • Enforce strict security reviews and automated static analysis (SAST) checks.
CWE-827: Common Weakness Enumeration Entry CWE-827 · DayBreach Sözlük · DayBreach