CWE-1287 Base Incompleto

Improper Validation of Specified Type of Input

This vulnerability occurs when software expects a specific type of data as input but fails to properly check that the incoming data actually matches that type.

Definição

What is CWE-1287?

This vulnerability occurs when software expects a specific type of data as input but fails to properly check that the incoming data actually matches that type.
When software doesn't verify that input matches the expected data type, attackers can feed it malformed data. This can trigger system errors, force the application to behave incorrectly, or expose hidden security flaws that would normally be inaccessible with properly typed input. This issue is most common in programming languages that are not strictly type-safe or that allow explicit conversion between data types. Developers must implement explicit validation checks to ensure input conforms to the expected type before processing it, as relying on implicit assumptions creates a significant security gap.
Impacto no mundo real

Real-world CVEs caused by CWE-1287

  • Large language model (LLM) management tool does not validate the format of a digest value (CWE-1287) from a private, untrusted model registry, enabling relative path traversal (CWE-23), a.k.a. Probllama

  • SQL injection through an ID that was supposed to be numeric.

Como os atacantes a exploram

Trajeto do atacante passo a passo

  1. 1

    Identificar um caminho de código que trata input não confiável sem validação.

  2. 2

    Criar um payload que explora o comportamento inseguro — injeção, traversal, overflow ou abuso de lógica.

  3. 3

    Entregar o payload através de um pedido normal e observar a reação da aplicação.

  4. 4

    Iterar até que a resposta exponha dados, execute código do atacante ou escale privilégios.

Exemplo de código vulnerável

Vulnerable pseudo

A MITRE não publicou um exemplo de código para este CWE. O padrão abaixo é ilustrativo — consulte os Recursos para referências canónicas.

Vulnerável pseudo
// Example pattern — see MITRE for the canonical references.
function handleRequest(input) {
  // Untrusted input flows directly into the sensitive sink.
  return executeUnsafe(input);
}
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-1287

  • Implementation Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue." Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
Sinais de deteção

How to detect CWE-1287

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.

CWE-1287

Don't catalog this weakness. Prove it's reachable.

Plexicus turns CWE catalogs into evidence: every CWE-pattern is matched against your real code graph, reach is proven on a sandbox clone, and verified findings ship as reviewed PRs.

Perguntas frequentes

Frequently asked questions

O que é o CWE-1287?

This vulnerability occurs when software expects a specific type of data as input but fails to properly check that the incoming data actually matches that type.

Qual a gravidade do CWE-1287?

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-1287?

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

Como posso prevenir o CWE-1287?

Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and…

Como é que o Plexicus deteta e corrige o CWE-1287?

O motor SAST do Plexicus correlaciona a assinatura de fluxo de dados do CWE-1287 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-1287?

A MITRE publica a definição canónica em https://cwe.mitre.org/data/definitions/1287.html. Pode também consultar a documentação da OWASP e do NIST para orientações adjacentes.

Fraquezas relacionadas

Weaknesses related to CWE-1287

CWE-20 Pai

Improper Input Validation

This vulnerability occurs when an application accepts data from an external source but fails to properly verify that the data is safe and…

CWE-102 Irmão

Struts: Duplicate Validation Forms

This vulnerability occurs when an application defines multiple Struts validation forms with identical names. The framework then…

CWE-103 Irmão

Struts: Incomplete validate() Method Definition

This vulnerability occurs in a Struts application when a validator form either completely omits a validate() method or includes one but…

CWE-104 Irmão

Struts: Form Bean Does Not Extend Validation Class

This vulnerability occurs in Apache Struts applications when a form bean class does not properly extend the framework's validation class.…

CWE-105 Irmão

Struts: Form Field Without Validator

This vulnerability occurs when a Struts application form contains an input field that lacks a corresponding validator, leaving it open to…

CWE-106 Irmão

Struts: Plug-in Framework not in Use

This weakness occurs when a Java application, particularly one using the Struts framework, does not implement a structured input…

CWE-107 Irmão

Struts: Unused Validation Form

This vulnerability occurs when a Struts application contains validation form definitions that are no longer linked to any active form or…

CWE-108 Irmão

Struts: Unvalidated Action Form

In Apache Struts, every Action Form that processes user input must have a corresponding validation form configured. Missing this…

CWE-109 Irmão

Struts: Validator Turned Off

This vulnerability occurs when an application built with Apache Struts intentionally disables its built-in validation framework. By…

Pronto para validar o que importa?

Pronto para validar o que importa.

O Plexicus é Proof-Driven AppSec: achados validados, compreensão contextual e remediação revisada — ancorada em evidência, escopada com você.

Qualificação

Verifique se o AI Swarm Pentest se adequa ao seu ambiente.

Partilhe o contexto mínimo. Vamos rever o escopo e indicar o próximo passo comercial.

Antes de enviar — verifique se se encaixa

0 / 280

Sem compromisso. Se não se encaixa, dizemos.

SAMPLE HANDOVER · ILLUSTRATIVE

Sample evidence handover

A trimmed view of what your team receives at the end of an AI Swarm Pentest engagement. Real engagements include full technical evidence, executive narrative, and a remediation plan.

VALIDATED FINDING Evidence attached

Server-Side Request Forgery in webhooks/receiver

demo-project/sample-app · src/webhooks/receiver.py:42

SeverityHigh CVSS 3.18.6 Priority79 Confirmedvia replay

Untrusted caller-supplied URLs reach an internal egress without an allowlist. Replayed in a sandbox against a fresh authorized target — the same control was validated to fail twice.

REVIEWER-READY REMEDIATION Merge-ready PR

Validate the target URL against an allowlist of permitted hostnames. Reject private/internal IP ranges. Enforce HTTPS only.

plexicus/remediation/webhooks-ssrf 3 changed · 0 new files
42resp = requests.get(target_url)
42+if not is_allowed_host(target_url):
43+  raise WebhookRejected(target_url)
44+resp = requests.get(target_url, timeout=5)
Every engagement hands over:
  • Executive briefing
  • Validated findings list
  • Merge-ready PRs
  • Compliance mapping (NIS2 · DORA · CRA)
Ronda privada Para investidores