계: Input Validation and Representation
입력 검증 및 표현 문제는 메타 문자, 대체 인코딩 및 숫자 표현 때문에 발생합니다. 보안 문제는 입력을 신뢰하기 때문에 발생합니다. 문제로는 "Buffer Overflows", "Cross-Site Scripting" 공격, "SQL Injection", 그 외 여러 가지가 있습니다.
OGNL Expression Injection
Abstract
확인되지 않은 OGNL 식을 평가하면 원격 코드 실행이 발생할 수 있습니다.
Explanation
OGNL(Object-Graph Navigation Language)은 Java용 오픈 소스 EL(표현 언어)로, Struts 2
다음 예제에서는 응용 프로그램이 확인되지 않은 사용자 제어 데이터를 사용하여 OGNL 식을 생성하고 평가합니다.
공격자는 다음 식을 제출하여 응용 프로그램 서버 컨텍스트에서 임의의 코드를 실행할 수 있습니다.
Value Stack 컨텍스트의 EL 식을 평가할 수 있도록 합니다. 확인되지 않은 식을 Value Stack과 비교하여 평가할 수 있게 하면 공격자가 액세스하여 시스템 변수를 수정하거나 임의의 코드를 실행할 수 있게 됩니다.다음 예제에서는 응용 프로그램이 확인되지 않은 사용자 제어 데이터를 사용하여 OGNL 식을 생성하고 평가합니다.
OgnlContext ctx = new OgnlContext();
String expression = request.getParameter("input");
Object expr = Ognl.parseExpression(expression);
Object value = Ognl.getValue(expr, ctx, root);
System.out.println("Value: " + value);
공격자는 다음 식을 제출하여 응용 프로그램 서버 컨텍스트에서 임의의 코드를 실행할 수 있습니다.
(#rt = @java.lang.Runtime@getRuntime(),#rt.exec("calc.exe"))
References
[1] Apache Commons OGNL - Object-Graph Navigation Library
[2] Meder Kydyraliev Milking a horse or executing remote code in modern Java frameworks
[3] Standards Mapping - Common Weakness Enumeration CWE ID 94, CWE ID 95
[4] Standards Mapping - Common Weakness Enumeration Top 25 2019 [18] CWE ID 094
[5] Standards Mapping - Common Weakness Enumeration Top 25 2020 [17] CWE ID 094
[6] Standards Mapping - Common Weakness Enumeration Top 25 2022 [25] CWE ID 094
[7] Standards Mapping - Common Weakness Enumeration Top 25 2023 [23] CWE ID 094
[8] Standards Mapping - Common Weakness Enumeration Top 25 2024 [11] CWE ID 094
[9] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-002754
[10] Standards Mapping - FIPS200 SI
[11] Standards Mapping - General Data Protection Regulation (GDPR) Indirect Access to Sensitive Data
[12] Standards Mapping - NIST Special Publication 800-53 Revision 4 SI-10 Information Input Validation (P1)
[13] Standards Mapping - NIST Special Publication 800-53 Revision 5 SI-10 Information Input Validation
[14] Standards Mapping - OWASP Application Security Verification Standard 4.0 5.2.4 Sanitization and Sandboxing Requirements (L1 L2 L3), 5.2.5 Sanitization and Sandboxing Requirements (L1 L2 L3), 5.2.8 Sanitization and Sandboxing Requirements (L1 L2 L3), 5.3.6 Output Encoding and Injection Prevention Requirements (L1 L2 L3)
[15] Standards Mapping - OWASP Mobile 2014 M7 Client Side Injection
[16] Standards Mapping - OWASP Mobile 2024 M4 Insufficient Input/Output Validation
[17] Standards Mapping - OWASP Top 10 2004 A6 Injection Flaws
[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 6.5.6
[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, Control Objective B.3.1 - Terminal Software Attack Mitigation, Control Objective B.3.1.1 - Terminal Software Attack Mitigation
[34] 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
[35] Standards Mapping - SANS Top 25 2009 Risky Resource Management - CWE ID 094
[36] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP3510 CAT I, APP3570 CAT I
[37] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP3510 CAT I, APP3570 CAT I
[38] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP3510 CAT I, APP3570 CAT I
[39] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP3510 CAT I, APP3570 CAT I
[40] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP3510 CAT I, APP3570 CAT I
[41] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP3510 CAT I, APP3570 CAT I
[42] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP3510 CAT I, APP3570 CAT I
[43] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-002560 CAT I
[44] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-002560 CAT I
[45] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-002560 CAT I
[46] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-002560 CAT I
[47] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-002560 CAT I
[48] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-002560 CAT I
[49] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-002560 CAT I
[50] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-002560 CAT I
[51] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-002560 CAT I
[52] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-002560 CAT I
[53] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-002560 CAT I
[54] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-002560 CAT I
[55] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-002560 CAT I
[56] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-002530 CAT II, APSC-DV-002560 CAT I
[57] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-002530 CAT II, APSC-DV-002560 CAT I
[58] Standards Mapping - Web Application Security Consortium Version 2.00 Improper Input Handling (WASC-20)
desc.dataflow.java.ognl_expression_injection