界: Input Validation and Representation
入力の検証や表現の問題は、メタキャラクター、代替エンコーディング、数値表現などによって引き起こされます。セキュリティの問題は、入力を信頼することに起因します。この問題に含まれるのは、「Buffer Overflow」、「Cross-Site Scripting」攻撃、「SQL Injection」などです。
OGNL Expression Injection
Abstract
未検証の OGNL 式の評価はリモートでのコード実行に繋がる可能性があります。
Explanation
OGNL (Object-Graph Navigation Language) は Java 用のオープンソース EL (Expression Language) であり、これを使って、Struts 2 の
次の例では、アプリケーションが、ユーザーが制御する未検証のデータを使用して、OGNL 式を作成および評価します。
攻撃者は、アプリケーション サーバーのコンテキストで任意のコードを実行するために次の式を実行できます。
Value Stack
のコンテキストで EL 式を評価できます。 Value Stack
に対する未検証の式の評価を許可することにより、攻撃者がシステム変数にアクセスして改変したり、任意のコードを実行したりできるようになります。次の例では、アプリケーションが、ユーザーが制御する未検証のデータを使用して、OGNL 式を作成および評価します。
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);
攻撃者は、アプリケーション サーバーのコンテキストで任意のコードを実行するために次の式を実行できます。
(#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