Reino: Input Validation and Representation

Problemas de validação e representação da entrada são causados por metacaracteres, codificações alternativas e representações numéricas. Confiar na entrada resulta em problemas de segurança. Os problemas incluem: “Buffer Overflows”, ataques de “Cross-Site Scripting”, “SQL Injection”, entre outros.

Dynamic Code Evaluation: Serializable Delegate

C#/VB.NET/ASP.NET

Abstract

O campo Delegate serializável pode introduzir vulnerabilidades de execução de código arbitrário durante ou após a desserialização dessa classe.

Explanation

O tipo Delegate é utilizado para manter a referência a uma chamada de método que pode ser invocada mais tarde no código do usuário. O .NET usa a serialização personalizada durante a serialização de tipos Delegate e utiliza a classe System.DelegateSerializationHolder para armazenar as informações de método que estão anexadas ou inscritas em um Delegate. Portanto, o fluxo serializado do objeto Delegate não é adequado para o armazenamento persistente ou para transmiti-lo para o aplicativo remoto, pois um invasor poderia substituir as informações de método por informações que apontam para os gráficos de objetos mal-intencionados, que podem causar uma vulnerabilidade de execução de código arbitrário quando invocados durante ou após a desserialização.

Exemplo 1: A seguinte classe contém um campo serializado Delegate e está sendo invocada no método Executor:


      ...
      [Serializable]
      class DynamicRunnner
      {
          Delegate _del;
          string[] _arg;
          public DynamicRunnner(Delegate dval, params string[] arg)
          {
              _del = dval;
              _arg = arg;
          }
          public bool Executor()
          {
              return (bool)_del.DynamicInvoke(_arg);
          }
      }
      ...

Se o desenvolvedor desserializar um fluxo não confiável da classe mencionada no Example 1, pode ser que um invasor consiga substituir as informações de método por informações que apontem para Process.Start. Isso causará a criação de um processo arbitrário quando o método Executor for chamado.

References

[1] Security Considerations for Data

[2] James Forshaw Are you my Type? Breaking .NET Through Serialization

[3] David LeBlanc, Michael Howard Writing Secure Code (2nd Edition) Microsoft Press

[4] Standards Mapping - CIS Azure Kubernetes Service Benchmark 4

[5] Standards Mapping - CIS Microsoft Azure Foundations Benchmark complete

[6] Standards Mapping - CIS Amazon Elastic Kubernetes Service Benchmark 4

[7] Standards Mapping - CIS Amazon Web Services Foundations Benchmark 4

[8] Standards Mapping - CIS Google Cloud Computing Platform Benchmark complete

[9] Standards Mapping - CIS Google Kubernetes Engine Benchmark integrity

[10] Standards Mapping - CIS Kubernetes Benchmark complete

[11] Standards Mapping - Common Weakness Enumeration CWE ID 502

[12] Standards Mapping - Common Weakness Enumeration Top 25 2019 [23] CWE ID 502

[13] Standards Mapping - Common Weakness Enumeration Top 25 2020 [21] CWE ID 502

[14] Standards Mapping - Common Weakness Enumeration Top 25 2021 [13] CWE ID 502

[15] Standards Mapping - Common Weakness Enumeration Top 25 2022 [12] CWE ID 502

[16] Standards Mapping - Common Weakness Enumeration Top 25 2023 [15] CWE ID 502

[17] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-001764, CCI-001774, CCI-002754

[18] Standards Mapping - FIPS200 SI

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

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

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

[22] Standards Mapping - OWASP Top 10 2004 A6 Injection Flaws

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

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

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

[26] Standards Mapping - OWASP Top 10 2017 A8 Insecure Deserialization

[27] Standards Mapping - OWASP Top 10 2021 A08 Software and Data Integrity Failures

[28] Standards Mapping - OWASP Application Security Verification Standard 4.0 1.5.2 Input and Output Architectural Requirements (L2 L3), 5.5.1 Deserialization Prevention Requirements (L1 L2 L3), 5.5.3 Deserialization Prevention Requirements (L1 L2 L3)

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

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

[31] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 Requirement 6.5.6

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

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

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

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

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

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

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

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

[40] 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

[41] 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, Control Objective C.3.5 - Web Software Attack Mitigation

[42] Standards Mapping - SANS Top 25 2009 Insecure Interaction - CWE ID 116

[43] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP3510 CAT I, APP3570 CAT I

[44] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP3510 CAT I, APP3570 CAT I

[45] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP3510 CAT I, APP3570 CAT I

[46] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP3510 CAT I, APP3570 CAT I

[47] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP3510 CAT I, APP3570 CAT I

[48] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP3510 CAT I, APP3570 CAT I

[49] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP3510 CAT I, APP3570 CAT I

[50] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[51] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[52] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[53] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[54] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[55] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[56] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[57] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[58] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[59] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[60] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[61] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[62] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002560 CAT I

[63] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-001480 CAT II, APSC-DV-001490 CAT II, APSC-DV-002530 CAT II, APSC-DV-002560 CAT I

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

desc.structural.dotnet.dynamic_code_evaluation_serializable_delegate