계: Environment

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Weak XML Schema: Lax Processing

Universal

Abstract

processContents 속성이 lax 또는 skip으로 설정되면 와일드카드 요소 및 속성에 대해 입력 검증이 수행되지 않습니다.

Explanation

엄격한 입력 검증을 적용하지 않는 스키마는 임의의 요소 또는 속성이 검증되도록 할 수 있습니다. 이는 공격자가 시스템에 악성 문서를 제공할 수 있는 가능성을 열어줍니다.

예제 1: 검증을 위해 다음 2가지 스키마의 사용을 상상해 보십시오.

스키마 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>

스키마 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>

스키마 1은 http://itemInfo 네임스페이스에서 임의의 태그가 검증되도록 허용하므로 다음 XML이 검증을 통과할 수 있습니다.


<?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>

앞선 XML에는 스키마 2에 정의되지 않은 itemInfo:price 태그가 포함되어 있습니다. 결과적으로, Shoes에 대해 $1의 가격을 설정하도록 이 XML 문서의 고객을 속일 수 있습니다.

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 - Web Application Security Consortium Version 2.00 Improper Input Handling (WASC-20)

desc.config.xml.weak_xml_schema_lax_processing