Reino: Environment

Esta sección incluye todo lo que está fuera del código fuente pero aun así es importante para la seguridad del producto que se está creando. Dado que todas las cuestiones incluidas en esta sección no están directamente relacionadas con el código fuente, las hemos separado de las demás secciones.

Weak XML Schema: Lax Processing

Universal

Abstract

Cuando el atributo processContents se establece en lax o skip, no se realiza ninguna validación de entrada de los elementos y atributos comodín.

Explanation

Un esquema que no impone una validación de entrada estricta puede permitir la validación de elementos o atributos arbitrarios. Esto abre la puerta a que un atacante suministre un documento malintencionado al sistema.

Ejemplo 1: Imagine que está utilizando los siguientes dos esquemas de validación.

Esquema 1:


<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"  >
  <xs:element name="cart" >
    <xs:complexType>
      <xs:sequence>
	<xs:element name="itemID" maxOccurs="1" />
	<xs:any namespace="http://itemInfo" processContents="lax" minOccurs="1" maxOccurs="5"/>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>

Esquema 2:


<?xml version="1.0"?>
<xsd:schema targetNamespace="http://itemInfo" xmlns:xsd="http://www.w3.org/2001/XMLSchema" >
  <xsd:element name="name" type="xsd:string"/>
  <xsd:element name="description" type="xsd:string"/>
</xsd:schema>

El esquema 1 permite que las etiquetas arbitrarias del espacio de nombres http://itemInfo se validen en él, lo que hace posible que el siguiente XML pase la validación.


<?xml version=\"1.0\" ?>
<cart xmlns:itemInfo="http://itemInfo">
  <itemID>123</itemID>
  <itemInfo:name>Shoes</itemInfo:name>
  <itemInfo:description>Black Shoes</itemInfo:description>
  <itemInfo:price>1.00</itemInfo:price>
</cart>

El XML anterior contiene una etiqueta itemInfo:price que no está definida en el Esquema 2. Como resultado, es posible engañar al consumidor de este documento XML para que fije un precio de 1$ para Shoes.

References

[1] XML Schema Part 1: Structures Second Edition W3C

[2] Standards Mapping - Common Weakness Enumeration CWE ID 20

[3] Standards Mapping - Common Weakness Enumeration Top 25 2021 [4] CWE ID 020

[4] Standards Mapping - Common Weakness Enumeration Top 25 2022 [4] CWE ID 020

[5] Standards Mapping - Common Weakness Enumeration Top 25 2023 [6] CWE ID 020

[6] Standards Mapping - Common Weakness Enumeration Top 25 2024 [12] CWE ID 020

[7] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-001310, CCI-002754

[8] Standards Mapping - FIPS200 SI

[9] Standards Mapping - General Data Protection Regulation (GDPR) Indirect Access to Sensitive Data

[10] Standards Mapping - NIST Special Publication 800-53 Revision 4 SI-10 Information Input Validation (P1)

[11] Standards Mapping - NIST Special Publication 800-53 Revision 5 SI-10 Information Input Validation

[12] Standards Mapping - OWASP API 2023 API8 Security Misconfiguration

[13] Standards Mapping - OWASP Application Security Verification Standard 4.0 5.1.3 Input Validation Requirements (L1 L2 L3), 5.1.4 Input Validation Requirements (L1 L2 L3)

[14] Standards Mapping - OWASP Mobile 2014 M7 Client Side Injection

[15] Standards Mapping - OWASP Mobile 2024 M8 Security Misconfiguration

[16] Standards Mapping - OWASP Mobile Application Security Verification Standard 2.0 MASVS-CODE-4

[17] Standards Mapping - OWASP Top 10 2004 A1 Unvalidated Input

[18] Standards Mapping - OWASP Top 10 2007 A2 Injection Flaws

[19] Standards Mapping - OWASP Top 10 2010 A1 Injection

[20] Standards Mapping - OWASP Top 10 2013 A1 Injection

[21] Standards Mapping - OWASP Top 10 2017 A1 Injection

[22] Standards Mapping - OWASP Top 10 2021 A03 Injection

[23] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 Requirement 6.5.1

[24] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 Requirement 6.3.1.1, Requirement 6.5.2

[25] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 Requirement 6.5.1

[26] Standards Mapping - Payment Card Industry Data Security Standard Version 3.0 Requirement 6.5.1

[27] Standards Mapping - Payment Card Industry Data Security Standard Version 3.1 Requirement 6.5.1

[28] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2 Requirement 6.5.1

[29] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 6.5.1

[30] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0 Requirement 6.2.4

[31] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0.1 Requirement 6.2.4

[32] Standards Mapping - Payment Card Industry Software Security Framework 1.0 Control Objective 4.2 - Critical Asset Protection

[33] Standards Mapping - Payment Card Industry Software Security Framework 1.1 Control Objective 4.2 - Critical Asset Protection

[34] Standards Mapping - Payment Card Industry Software Security Framework 1.2 Control Objective 4.2 - Critical Asset Protection

[35] Standards Mapping - SANS Top 25 2009 Insecure Interaction - CWE ID 020

[36] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP3510 CAT I

[37] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP3510 CAT I

[38] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP3510 CAT I

[39] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP3510 CAT I

[40] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP3510 CAT I

[41] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP3510 CAT I

[42] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP3510 CAT I

[43] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[44] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[45] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[46] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[47] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[48] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[49] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[50] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[51] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[52] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[53] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[54] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[55] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[56] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[57] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[58] Standards Mapping - Security Technical Implementation Guide Version 6.2 APSC-DV-002550 CAT I, APSC-DV-002560 CAT I

[59] Standards Mapping - Web Application Security Consortium Version 2.00 Improper Input Handling (WASC-20)

desc.config.xml.weak_xml_schema_lax_processing