Reino: Input Validation and Representation

Los problemas de validación y representación de entradas están causados por metacaracteres, codificaciones alternativas y representaciones numéricas. Los problemas de seguridad surgen de entradas en las que se confía. Estos problemas incluyen: «desbordamientos de búfer», ataques de «scripts de sitios», "SQL injection" y muchas otras acciones.

Cross-Site Scripting: Handlebars Helper

JavaScript/TypeScript

Abstract

El envío de datos no validados a un explorador web puede dar lugar a que este ejecute código malintencionado.

Explanation

Las vulnerabilidades Cross-Site Scripting (XSS) se producen cuando:

1. Los datos entran en una aplicación web a través de un origen no confiable. Con Handlebars, puede crear auxiliares personalizados que se pueden usar para modificar plantillas.

2. Los datos se incluyen en el contenido dinámico que se inserta en una plantilla antes de procesarse sin validación. En el caso del auxiliar de Handlebars, el contenido malintencionado se procesa como la salida de la plantilla.

El contenido malintencionado en un auxiliar de Handlebars adopta la forma de un segmento de código JavaScript o cualquier otro tipo de código que el explorador ejecute. Dado que la salida de una plantilla de Handlebars suele ser contenido HTML que se pasa al explorador, cualquier contenido potencialmente malicioso debe tratarse como no seguro y validarse.

Ejemplo 1: Considere el siguiente código auxiliar de Handlebars:


Handlebars.registerHelper('bolden', function (aString) {
  return new Handlebars.SafeString("" + aString + "")
})
// ...
let template = Handlebars.compile('{{bolden someArgument}}')
myElem.innerHTML = template({someArgument: userInput})

El auxiliar bolden recibe los datos controlados por el usuario userInput. Aunque el uso de llaves dobles ({{ y }}) generalmente significa que la salida estará codificada en HTML, en este escenario, el auxiliar bolden anula cualquier validación al pasar la entrada a new Handlebars.SafeString(), lo que hace que la entrada se procese como HTML normal. Cuando el HTML regresa de template(), se pasa a la propiedad innerHTML que conduce a un XSS basado en DOM.

References

[1] Understanding Malicious Content Mitigation for Web Developers CERT

[2] HTML 4.01 Specification W3

[3] Standards Mapping - Common Weakness Enumeration CWE ID 79, CWE ID 80

[4] Standards Mapping - Common Weakness Enumeration Top 25 2019 [2] CWE ID 079

[5] Standards Mapping - Common Weakness Enumeration Top 25 2020 [1] CWE ID 079

[6] Standards Mapping - Common Weakness Enumeration Top 25 2021 [2] CWE ID 079

[7] Standards Mapping - Common Weakness Enumeration Top 25 2022 [2] CWE ID 079

[8] Standards Mapping - Common Weakness Enumeration Top 25 2023 [2] CWE ID 079

[9] Standards Mapping - Common Weakness Enumeration Top 25 2024 [1] CWE ID 079

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

[11] Standards Mapping - FIPS200 SI

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

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

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

[15] Standards Mapping - OWASP Application Security Verification Standard 4.0 5.3.3 Output Encoding and Injection Prevention Requirements (L1 L2 L3), 5.3.6 Output Encoding and Injection Prevention Requirements (L1 L2 L3)

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

[17] Standards Mapping - OWASP Mobile 2024 M4 Insufficient Input/Output Validation

[18] Standards Mapping - OWASP Top 10 2004 A4 Cross Site Scripting

[19] Standards Mapping - OWASP Top 10 2007 A1 Cross Site Scripting (XSS)

[20] Standards Mapping - OWASP Top 10 2010 A2 Cross-Site Scripting (XSS)

[21] Standards Mapping - OWASP Top 10 2013 A3 Cross-Site Scripting (XSS)

[22] Standards Mapping - OWASP Top 10 2017 A7 Cross-Site Scripting (XSS)

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

[24] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 Requirement 6.5.4

[25] Standards Mapping - Payment Card Industry Data Security Standard Version 1.2 Requirement 6.3.1.1, Requirement 6.5.1

[26] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 Requirement 6.5.7

[27] Standards Mapping - Payment Card Industry Data Security Standard Version 3.0 Requirement 6.5.7

[28] Standards Mapping - Payment Card Industry Data Security Standard Version 3.1 Requirement 6.5.7

[29] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2 Requirement 6.5.7

[30] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 6.5.7

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

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

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

[34] Standards Mapping - Payment Card Industry Software Security Framework 1.1 Control Objective 4.2 - Critical Asset Protection, Control Objective B.3.1 - Terminal Software Attack Mitigation, Control Objective B.3.1.1 - Terminal Software Attack Mitigation

[35] Standards Mapping - Payment Card Industry Software Security Framework 1.2 Control Objective 4.2 - Critical Asset Protection, Control Objective B.3.1 - Terminal Software Attack Mitigation, Control Objective B.3.1.1 - Terminal Software Attack Mitigation, Control Objective C.3.2 - Web Software Attack Mitigation

[36] Standards Mapping - SANS Top 25 2009 Insecure Interaction - CWE ID 079

[37] Standards Mapping - SANS Top 25 2010 Insecure Interaction - CWE ID 079

[38] Standards Mapping - SANS Top 25 2011 Insecure Interaction - CWE ID 079

[39] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP3510 CAT I, APP3580 CAT I

[40] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP3510 CAT I, APP3580 CAT I

[41] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP3510 CAT I, APP3580 CAT I

[42] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP3510 CAT I, APP3580 CAT I

[43] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP3510 CAT I, APP3580 CAT I

[44] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP3510 CAT I, APP3580 CAT I

[45] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP3510 CAT I, APP3580 CAT I

[46] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[47] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[48] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[49] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[50] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[51] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[52] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[53] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[54] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[55] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[56] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[57] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[58] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-002490 CAT I, APSC-DV-002560 CAT I

[59] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-002490 CAT I, APSC-DV-002530 CAT II, APSC-DV-002560 CAT I

[60] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-002490 CAT I, APSC-DV-002530 CAT II, APSC-DV-002560 CAT I

[61] Standards Mapping - Web Application Security Consortium Version 2.00 Cross-Site Scripting (WASC-08)

[62] Standards Mapping - Web Application Security Consortium 24 + 2 Cross-Site Scripting

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