CWE-441 Detalhe

CWE-441

Unintended Proxy or Intermediary ('Confused Deputy')
Draft
2006-07-19
00h00 +00:00
2025-12-11
00h00 +00:00
Notificações para um CWE
Fique informado sobre quaisquer alterações para um CWE específico.
Gerenciar notificações

Nome: Unintended Proxy or Intermediary ('Confused Deputy')

The product receives a request, message, or directive from an upstream component, but the product does not sufficiently preserve the original source of the request before forwarding the request to an external actor that is outside of the product's control sphere. This causes the product to appear to be the source of the request, leading it to act as a proxy or other intermediary between the upstream component and the external actor.

Informações Gerais

Modos de Introdução

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

Plataformas Aplicáveis

Linguagem

Class: Not Language-Specific (Undetermined)

Sistemas Operacionais

Class: Not OS-Specific (Undetermined)

Arquiteturas

Class: Not Architecture-Specific (Undetermined)

Tecnologias

Class: Not Technology-Specific (Undetermined)

Consequências Comuns

Escopo Impacto Probabilidade
Non-Repudiation
Access Control
Gain Privileges or Assume Identity, Hide Activities, Execute Unauthorized Code or Commands

Exemplos Observados

Referências Descrição

CVE-1999-0017

FTP bounce attack. The design of the protocol allows an attacker to modify the PORT command to cause the FTP server to connect to other machines besides the attacker's.

CVE-1999-0168

RPC portmapper could redirect service requests from an attacker to another entity, which thinks the requests came from the portmapper.

CVE-2005-0315

FTP server does not ensure that the IP address in a PORT command is the same as the FTP user's session, allowing port scanning by proxy.

CVE-2002-1484

Web server allows attackers to request a URL from another server, including other ports, which allows proxied scanning.

CVE-2004-2061

CGI script accepts and retrieves incoming URLs.

CVE-2001-1484

Bounce attack allows access to TFTP from trusted side.

CVE-2010-1637

Web-based mail program allows internal network scanning using a modified POP3 port number.

CVE-2009-0037

URL-downloading library automatically follows redirects to file:// and scp:// URLs

Mitigações Potenciais

Phases : Architecture and Design
Enforce the use of strong mutual authentication mechanism between the two parties.
Phases : Architecture and Design
Whenever a product is an intermediary or proxy for transactions between two other components, the proxy core should not drop the identity of the initiator of the transaction. The immutability of the identity of the initiator must be maintained and should be forwarded all the way to the target.

Métodos de Detecção

Automated Static Analysis

Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
Eficácia : High

Notas de Mapeamento de Vulnerabilidade

Justificativa : This CWE entry is a Class and might have Base-level children that would be more appropriate
Comentário : Examine children of this entry to see if there is a better fit

Padrões de Ataque Relacionados

CAPEC-ID Nome do Padrão de Ataque
CAPEC-219 XML Routing Detour Attacks
An attacker subverts an intermediate system used to process XML content and forces the intermediate to modify and/or re-route the processing of the content. XML Routing Detour Attacks are Adversary in the Middle type attacks (CAPEC-94). The attacker compromises or inserts an intermediate system in the processing of the XML message. For example, WS-Routing can be used to specify a series of nodes or intermediaries through which content is passed. If any of the intermediate nodes in this route are compromised by an attacker they could be used for a routing detour attack. From the compromised system the attacker is able to route the XML process to other nodes of their choice and modify the responses so that the normal chain of processing is unaware of the interception. This system can forward the message to an outside entity and hide the forwarding and processing from the legitimate processing systems by altering the header information.
CAPEC-465 Transparent Proxy Abuse
A transparent proxy serves as an intermediate between the client and the internet at large. It intercepts all requests originating from the client and forwards them to the correct location. The proxy also intercepts all responses to the client and forwards these to the client. All of this is done in a manner transparent to the client.

Notas

This weakness has a chaining relationship with CWE-668 (Exposure of Resource to Wrong Sphere) because the proxy effectively provides the attacker with access to the target's resources that the attacker cannot directly obtain.
This could possibly be considered as an emergent resource.
It could be argued that the "confused deputy" is a fundamental aspect of most vulnerabilities that require an active attacker. Even for common implementation issues such as buffer overflows, SQL injection, OS command injection, and path traversal, the vulnerable program already has the authorization to run code or access files. The vulnerability arises when the attacker causes the program to run unexpected code or access unexpected files.

Referências

REF-432

The Confused Deputy (or why capabilities might have been invented)
Norm Hardy.
http://www.cap-lore.com/CapTheory/ConfusedDeputy.html

REF-1125

Validation Vulnerabilities
moparisthebest.
https://mailarchive.ietf.org/arch/msg/acme/s6Q5PdJP48LEUwgzrVuw_XPKCsM/

Submissão

Nome Organização Data Data de lançamento Version
PLOVER 2006-07-19 +00:00 2006-07-19 +00:00 Draft 3

Modificações

Nome Organização Data Comentário
Eric Dalci Cigital 2008-07-01 +00:00 updated Potential_Mitigations, Time_of_Introduction
CWE Content Team MITRE 2008-09-08 +00:00 updated Relationships, Observed_Example, Other_Notes, Taxonomy_Mappings
CWE Content Team MITRE 2008-11-24 +00:00 updated Maintenance_Notes, Relationships, Taxonomy_Mappings, Time_of_Introduction
CWE Content Team MITRE 2010-02-16 +00:00 updated Taxonomy_Mappings
CWE Content Team MITRE 2010-04-05 +00:00 updated Related_Attack_Patterns
CWE Content Team MITRE 2010-06-21 +00:00 updated Other_Notes
CWE Content Team MITRE 2011-06-01 +00:00 updated Common_Consequences
CWE Content Team MITRE 2011-06-27 +00:00 updated Common_Consequences
CWE Content Team MITRE 2012-05-11 +00:00 updated Related_Attack_Patterns, Relationships
CWE Content Team MITRE 2012-10-30 +00:00 updated Potential_Mitigations
CWE Content Team MITRE 2013-02-21 +00:00 updated Alternate_Terms, Applicable_Platforms, Description, Maintenance_Notes, Name, Observed_Examples, References, Relationship_Notes, Relationships, Theoretical_Notes, Type
CWE Content Team MITRE 2014-07-30 +00:00 updated Relationships
CWE Content Team MITRE 2015-12-07 +00:00 updated Relationships
CWE Content Team MITRE 2017-01-19 +00:00 updated Relationships
CWE Content Team MITRE 2017-11-08 +00:00 updated Modes_of_Introduction, Relationships
CWE Content Team MITRE 2019-06-20 +00:00 updated Relationships
CWE Content Team MITRE 2020-02-24 +00:00 updated Relationships
CWE Content Team MITRE 2020-08-14 +00:00 Per Intel Corporation suggestion, added language to be inclusive to hardware: updated Demonstrative_Examples, Description, Extended_Description, Applicable_Platforms, Potential_Mitigation, Common_Consequences, References
CWE Content Team MITRE 2020-08-20 +00:00 updated Applicable_Platforms, Common_Consequences, Demonstrative_Examples, Description, Potential_Mitigations, References, Relationships
CWE Content Team MITRE 2021-10-28 +00:00 updated Relationships
CWE Content Team MITRE 2022-10-13 +00:00 updated Related_Attack_Patterns
CWE Content Team MITRE 2023-04-27 +00:00 updated Detection_Factors, Relationships
CWE Content Team MITRE 2023-06-29 +00:00 updated Mapping_Notes
CWE Content Team MITRE 2025-12-11 +00:00 updated Alternate_Terms, Relationships, Weakness_Ordinalities