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-15 Base Incompleto
External Control of System or Configuration Setting
This vulnerability occurs when an application allows users to directly modify critical system settings or configuration values from an external source.
Definición
What is CWE-15?
This vulnerability occurs when an application allows users to directly modify critical system settings or configuration values from an external source.
When system settings like file paths, feature flags, or environment variables can be controlled by an external user, it breaks the fundamental trust between the application and its configuration. Attackers can exploit this to disrupt services, bypass security controls, or force the application to execute unintended and potentially malicious actions, leading to data loss or system compromise.
Preventing this requires rigorous validation of all configuration inputs and enforcing strict separation between user data and system controls. While SAST tools can catch the pattern, Plexicus uses AI to analyze the data flow and suggest the precise code fix—such as implementing allowlists or moving configurations to secure, internal sources—saving hours of manual remediation work across your codebase.
Impacto en el mundo real
Real-world CVEs caused by CWE-15
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
The following C code accepts a number as one of its command line parameters and sets it as the host ID of the current machine.
- 2
Although a process must be privileged to successfully invoke sethostid(), unprivileged users may be able to invoke the program. The code in this example allows user input to directly control the value of a system setting. If an attacker provides a malicious value for host ID, the attacker can misidentify the affected machine on the network or cause other unintended behavior.
- 3
The following Java code snippet reads a string from an HttpServletRequest and sets it as the active catalog for a database Connection.
- 4
In this example, an attacker could cause an error by providing a nonexistent catalog name or connect to an unauthorized portion of the database.
Ejemplo de código vulnerable
Vulnerable C
The following C code accepts a number as one of its command line parameters and sets it as the host ID of the current machine.
...
sethostid(argv[1]);
... 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-15
- Architecture and Design Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
- Implementation / Architecture and Design Because setting manipulation covers a diverse set of functions, any attempt at illustrating it will inevitably be incomplete. Rather than searching for a tight-knit relationship between the functions addressed in the setting manipulation category, take a step back and consider the sorts of system values that an attacker should not be allowed to control.
- Implementation / Architecture and Design In general, do not allow user-provided or otherwise untrusted data to control sensitive values. The leverage that an attacker gains by controlling these values is not always immediately obvious, but do not underestimate the creativity of the attacker.
Señales de detección
How to detect CWE-15
CWE-15
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.
Preguntas frecuentes ¿Qué es CWE-15?
¿Qué gravedad tiene CWE-15?
¿Qué lenguajes o plataformas se ven afectados por CWE-15?
¿Cómo puedo prevenir CWE-15?
¿Cómo detecta y corrige Plexicus CWE-15?
¿Dónde puedo aprender más sobre CWE-15?
Frequently asked questions
¿Qué es CWE-15?
This vulnerability occurs when an application allows users to directly modify critical system settings or configuration values from an external source.
¿Qué gravedad tiene CWE-15?
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-15?
MITRE lists the following affected platforms: Not Technology-Specific, ICS/OT.
¿Cómo puedo prevenir CWE-15?
Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to…
¿Cómo detecta y corrige Plexicus CWE-15?
El motor SAST de Plexicus detecta la firma de flujo de datos para CWE-15 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-15?
MITRE publica la definición canónica en https://cwe.mitre.org/data/definitions/15.html. También puedes consultar la documentación de OWASP y NIST para guías relacionadas.
Debilidades relacionadas
Weaknesses related to CWE-15
CWE-642 Padre
External Control of Critical State Data
This vulnerability occurs when an application stores security-sensitive state data in locations that unauthorized users can access and…
CWE-426 Hermano
Untrusted Search Path
This vulnerability occurs when an application relies on an external search path, provided by a user or environment, to find and load…
CWE-472 Hermano
External Control of Assumed-Immutable Web Parameter
This vulnerability occurs when a web application incorrectly trusts data that appears to be fixed or hidden from the user, such as values…
CWE-565 Hermano
Reliance on Cookies without Validation and Integrity Checking
This vulnerability occurs when an application uses cookies to make security decisions—like granting access or changing settings—but fails…
CWE-73 Hermano
External Control of File Name or Path
This vulnerability occurs when an application uses unvalidated user input to construct file or directory paths for filesystem operations.
Recursos
Further reading
- MITRE — CWE-15 oficial https://cwe.mitre.org/data/definitions/15.html
- Seven Pernicious Kingdoms: A Taxonomy of Software Security Errors https://samate.nist.gov/SSATTM_Content/papers/Seven%20Pernicious%20Kingdoms%20-%20Taxonomy%20of%20Sw%20Security%20Errors%20-%20Tsipenyuk%20-%20Chess%20-%20McGraw.pdf
¿Listo para validar lo que importa?
Listo para validar lo que importa.
Plexicus es Proof-Driven AppSec: hallazgos validados, comprensión contextual y remediación revisada — anclada en evidencia, acotada contigo.