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.)
CWE-523 Base Incompleto
Unprotected Transport of Credentials
This vulnerability occurs when a login page or authentication system transmits user credentials (like usernames and passwords) over a network without proper encryption, exposing them to interception.
Definición
What is CWE-523?
This vulnerability occurs when a login page or authentication system transmits user credentials (like usernames and passwords) over a network without proper encryption, exposing them to interception.
When credentials travel from a user's browser to your server without encryption, they are sent in plain text. Attackers on the same network can easily intercept this data using simple packet sniffing tools, leading directly to account compromise. This is a fundamental failure to protect the most sensitive part of the user session during its most vulnerable moment—transit.
To prevent this, you must enforce the use of strong, modern encryption for all authentication traffic. Always use HTTPS (TLS/SSL) for your entire login process and application, never falling back to HTTP for any requests containing credentials. Additionally, implement HTTP Strict Transport Security (HSTS) to instruct browsers to always use a secure connection, preventing accidental data leakage.
Impacto en el mundo real
Real-world CVEs caused by CWE-523
Todavía no hay CVEs públicos enlazados a esta CWE en el catálogo de MITRE.
Cómo lo explotan los atacantes
Ruta del atacante paso a paso
- 1
Identifica una ruta de código que maneje entrada no confiable sin validación.
- 2
Crea un payload que ejercite el comportamiento inseguro — inyección, traversal, overflow o abuso de lógica.
- 3
Envía el payload a través de una solicitud normal y observa la reacción de la aplicación.
- 4
Itera hasta que la respuesta filtre datos, ejecute código del atacante o escale privilegios.
Ejemplo de código vulnerable
Vulnerable pseudo
MITRE no ha publicado un ejemplo de código para esta CWE. El patrón siguiente es ilustrativo — consulta Recursos para referencias canónicas.
// Example pattern — see MITRE for the canonical references.
function handleRequest(input) {
// Untrusted input flows directly into the sensitive sink.
return executeUnsafe(input);
} Ejemplo de código seguro
Secure 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 prevención
How to prevent CWE-523
- Operation / System Configuration Enforce SSL use for the login page or any page used to transmit user credentials or other sensitive information. Even if the entire site does not use SSL, it MUST use SSL for login. Additionally, to help prevent phishing attacks, make sure that SSL serves the login page. SSL allows the user to verify the identity of the server to which they are connecting. If the SSL serves login page, the user can be certain they are talking to the proper end system. A phishing attack would typically redirect a user to a site that does not have a valid trusted server certificate issued from an authorized supplier.
Señales de detección
How to detect CWE-523
CWE-523
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Preguntas frecuentes ¿Qué es CWE-523?
¿Qué gravedad tiene CWE-523?
¿Qué lenguajes o plataformas se ven afectados por CWE-523?
¿Cómo puedo prevenir CWE-523?
¿Cómo detecta y corrige Plexicus CWE-523?
¿Dónde puedo aprender más sobre CWE-523?
Frequently asked questions
¿Qué es CWE-523?
This vulnerability occurs when a login page or authentication system transmits user credentials (like usernames and passwords) over a network without proper encryption, exposing them to interception.
¿Qué gravedad tiene CWE-523?
MITRE no ha publicado una calificación de probabilidad de explotación para esta debilidad. Trátala como de impacto medio hasta que tu modelo de amenazas demuestre lo contrario.
¿Qué lenguajes o plataformas se ven afectados por CWE-523?
MITRE no ha especificado plataformas afectadas para esta CWE — puede aplicar a la mayoría de los stacks de aplicaciones.
¿Cómo puedo prevenir CWE-523?
Enforce SSL use for the login page or any page used to transmit user credentials or other sensitive information. Even if the entire site does not use SSL, it MUST use SSL for login. Additionally, to help prevent phishing attacks, make sure that SSL serves the login page. SSL allows the user to verify the identity of the server to which they are connecting. If the SSL serves login page, the user can be certain they are talking to the proper end system. A phishing attack would typically redirect…
¿Cómo detecta y corrige Plexicus CWE-523?
El motor SAST de Plexicus detecta la firma de flujo de datos para CWE-523 en cada commit. Cuando hay coincidencia, nuestro agente Codex Remedium abre un PR de corrección con el código corregido, las pruebas y un resumen de una línea para el revisor.
¿Dónde puedo aprender más sobre CWE-523?
MITRE publica la definición canónica en https://cwe.mitre.org/data/definitions/523.html. También puedes consultar la documentación de OWASP y NIST para guías relacionadas.
Debilidades relacionadas
Weaknesses related to CWE-523
CWE-522 Padre
Insufficiently Protected Credentials
This vulnerability occurs when an application handles sensitive credentials like passwords or API keys in an insecure way, making them…
CWE-256 Hermano
Plaintext Storage of a Password
This vulnerability occurs when an application stores user passwords as readable text instead of using secure, one-way hashing. This…
CWE-257 Hermano
Storing Passwords in a Recoverable Format
This vulnerability occurs when an application stores user passwords in a format that can be easily reversed or decrypted back to their…
CWE-260 Hermano
Password in Configuration File
This vulnerability occurs when an application stores sensitive passwords directly within a configuration file, making them easily readable…
CWE-261 Hermano
Weak Encoding for Password
Using simple encoding like Base64 to hide a password provides no real security, as it can be easily reversed.
CWE-549 Hermano
Missing Password Field Masking
This vulnerability occurs when an application fails to hide password characters as they are typed, making them visible to anyone who can…
CWE-312 Par
Cleartext Storage of Sensitive Information
This vulnerability occurs when an application stores sensitive data like passwords, credit card numbers, or personal information in plain…
¿Listo para validar lo que importa?
Listo para validar lo que importa.
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