CWE-670 Classe Rascunho

Always-Incorrect Control Flow Implementation

This weakness occurs when a section of code is structured in a way that always executes incorrectly, regardless of input or conditions. The control flow logic is fundamentally flawed and does not…

Definição

What is CWE-670?

This weakness occurs when a section of code is structured in a way that always executes incorrectly, regardless of input or conditions. The control flow logic is fundamentally flawed and does not match the intended algorithm.

Unlike many security flaws that are triggered by unexpected or malicious data, this issue represents a permanent logic error in the code. The problematic path is always wrong, meaning the software will behave incorrectly every time that specific code segment runs. This is often the result of simple syntactic mistakes, like omitting curly braces in C-style languages, which changes which statements are included in a conditional block. For developers, this means the bug is not situational; it's a constant defect in the program's logic. Identifying these flaws requires carefully reviewing the intended algorithm against the actual code structure, as standard testing with varied inputs might not reveal the root cause—the logic itself is broken from the start.

Impacto no mundo real

Real-world CVEs caused by CWE-670

CVE-2021-3011

virtual interrupt controller in a virtualization product allows crash of host by writing a certain invalid value to a register, which triggers a fatal error instead of returning an error code

Como os atacantes a exploram

Trajeto do atacante passo a passo

1
This code queries a server and displays its status when a request comes from an authorized IP address.
2
This code redirects unauthorized users, but continues to execute code after calling http_redirect(). This means even unauthorized users may be able to access the contents of the page or perform a DoS attack on the server being queried. Also, note that this code is vulnerable to an IP address spoofing attack (CWE-212).
3
In this example, the programmer has indented the statements to call Do_X() and Do_Y(), as if the intention is that these functions are only called when the condition is true. However, because there are no braces to signify the block, Do_Y() will always be executed, even if the condition is false.
4
This might not be what the programmer intended. When the condition is critical for security, such as in making a security decision or detecting a critical error, this may produce a vulnerability.
5
In both of these examples, a message is printed based on the month passed into the function:

Exemplo de código vulnerável

Vulnerable PHP

This code queries a server and displays its status when a request comes from an authorized IP address.

Vulnerável PHP

$requestingIP = $_SERVER['REMOTE_ADDR'];
  if(!in_array($requestingIP,$ipAllowList)){
  	echo "You are not authorized to view this page";
  	http_redirect($errorPageURL);
  }
  $status = getServerStatus();
  echo $status;
```
...*

Exemplo de código seguro

Secure pseudo

Seguro pseudo

// Validate, sanitize, or use a safe API before reaching the sink.
function handleRequest(input) {
  const safe = validateAndEscape(input);
  return executeWithGuards(safe);
}

What changed: the unsafe sink is replaced (or the input is validated/escaped) so the same payload no longer triggers the weakness.

Lista de verificação de prevenção

How to prevent CWE-670

Architecture Use safe-by-default frameworks and APIs that prevent the unsafe pattern from being expressible.
Implementation Validate input at trust boundaries; use allowlists, not denylists.
Implementation Apply the principle of least privilege to credentials, file paths, and runtime permissions.
Testing Cover this weakness in CI: SAST rules + targeted unit tests for the data flow.
Operation Monitor logs for the runtime signals listed in the next section.

Sinais de deteção

How to detect CWE-670

SAST High

Executar análise estática (SAST) na base de código à procura do padrão inseguro no fluxo de dados.

DAST Moderate

Executar testes dinâmicos de segurança de aplicações (DAST) contra o endpoint em execução.

Runtime Moderate

Monitorizar os registos em tempo de execução para traços de exceção invulgares, input malformado ou tentativas de contornar a autorização.

Code review Moderate

Revisão de código: sinalizar qualquer novo código que trate input desta superfície sem usar os ajudantes validados do framework.

Correção automática do Plexicus

O Plexicus deteta automaticamente o CWE-670 e abre um PR de correção em menos de 60 segundos.

O Codex Remedium analisa cada commit, identifica esta fraqueza exata e entrega um pull request pronto para revisão com o patch. Sem tickets. Sem transferências.

Obter uma demonstração Experimente o Plexicus gratuitamente

Perguntas frequentes

Frequently asked questions

O que é o CWE-670?

Qual a gravidade do CWE-670?

A MITRE não publicou uma classificação de probabilidade de exploração para esta fraqueza. Trate-a como impacto médio até o seu modelo de ameaças provar o contrário.

Que linguagens ou plataformas são afetadas pelo CWE-670?

A MITRE não especificou as plataformas afetadas por este CWE — pode aplicar-se à maioria das stacks de aplicações.

Como posso prevenir o CWE-670?

Use safe-by-default frameworks, validate untrusted input at trust boundaries, and apply the principle of least privilege. Cover the data-flow signature in CI with SAST.

Como é que o Plexicus deteta e corrige o CWE-670?

O motor SAST do Plexicus correlaciona a assinatura de fluxo de dados do CWE-670 em cada commit. Quando é encontrada uma correspondência, o nosso agente Codex Remedium abre um PR de correção com o código corrigido, testes e um resumo de uma linha para o revisor.

Onde posso saber mais sobre o CWE-670?

A MITRE publica a definição canónica em https://cwe.mitre.org/data/definitions/670.html. Pode também consultar a documentação da OWASP e do NIST para orientações adjacentes.

Fraquezas relacionadas

Weaknesses related to CWE-670

CWE-691 Pai

Insufficient Control Flow Management

This vulnerability occurs when a program's execution flow isn't properly managed, allowing attackers to bypass critical checks, trigger…

CWE-1265 Irmão

Unintended Reentrant Invocation of Non-reentrant Code Via Nested Calls

This vulnerability occurs when a non-reentrant function is called, and during its execution, another call is triggered that unexpectedly…

CWE-1281 Irmão

Sequence of Processor Instructions Leads to Unexpected Behavior

Certain sequences of valid and invalid processor instructions can cause the CPU to lock up or behave unpredictably, often requiring a hard…

CWE-362 Irmão

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

A race condition occurs when multiple processes or threads access a shared resource simultaneously without proper coordination, creating a…

CWE-430 Irmão

Deployment of Wrong Handler

This vulnerability occurs when a system incorrectly assigns or routes an object to the wrong processing component.

CWE-431 Irmão

Missing Handler

This vulnerability occurs when a software component lacks the necessary code to properly handle an error or unexpected event.

CWE-662 Irmão

Improper Synchronization

This vulnerability occurs when a multi-threaded or multi-process application allows shared resources to be accessed by multiple threads or…

CWE-696 Irmão

Incorrect Behavior Order

This weakness occurs when a system executes multiple dependent actions in the wrong sequence, leading to unexpected and potentially…

CWE-705 Irmão

Incorrect Control Flow Scoping

This vulnerability occurs when a program fails to return execution to the correct point in the code after finishing a specific operation…

Recursos

Pare de pagar por desenvolvedor.
Comece a fechar o ciclo.

O Plexicus é o ASPM nativo de IA que verifica, filtra, corrige, pentesta e explica — de forma autónoma. Programadores ilimitados, repos ilimitados, ações de IA de utilização justa. Nível gratuito real, €269/mo anual quando estiver pronto.

Começar grátis Reservar uma demo