Kingdom: Input Validation and Representation
Input validation and representation problems ares caused by metacharacters, alternate encodings and numeric representations. Security problems result from trusting input. The issues include: "Buffer Overflows," "Cross-Site Scripting" attacks, "SQL Injection," and many others.
Setting Manipulation: Character Set
Abstract
Allowing external control of system settings can disrupt service or cause an application to behave in unexpected ways.
Explanation
Setting manipulation vulnerabilities occur when an attacker can control values that govern the behavior of the system, manage specific resources, or in some way affect the functionality of the application.
Allowing a user to control the character encoding used to parse the HTTP response of a given request can allow an attacker to evade certain validation mechanisms used for Cross-site Scripting.
The response character encoding is used by a web browser to decide how to interpret the characters in the body of the HTTP response. The most common encoding used by web applications today is
Example 1:
The previous string means nothing in most encoding types, and therefore is "safe", but when a victim views this under
Allowing a user to control the character encoding used to parse the HTTP response of a given request can allow an attacker to evade certain validation mechanisms used for Cross-site Scripting.
The response character encoding is used by a web browser to decide how to interpret the characters in the body of the HTTP response. The most common encoding used by web applications today is
UTF-8. The character set (charset) declaration is usually done through a header in the HTTP response or using the HTML <meta> tag. Only the application should control these declarations. If this declaration is controlled through user input, then an attacker can use this feature to modify the charset that the browser uses and modify the interpretation of the contents of the response. This can enable Cross-site Scripting attacks that would otherwise not have succeeded while using UTF-8 encoding.Example 1:
+ADw-script+AD4-alert(document.location)+ADw-/script+AD4
The previous string means nothing in most encoding types, and therefore is "safe", but when a victim views this under
utf-7 encoding, it is interpreted as valid HTML tag and, the script is executed.References
[1] Standards Mapping - Common Weakness Enumeration CWE ID 116
[2] Standards Mapping - DISA Control Correlation Identifier Version 2 CCI-001310, CCI-002754
[3] Standards Mapping - FIPS200 CM
[4] Standards Mapping - General Data Protection Regulation (GDPR) Indirect Access to Sensitive Data
[5] Standards Mapping - NIST Special Publication 800-53 Revision 4 SI-10 Information Input Validation (P1)
[6] Standards Mapping - NIST Special Publication 800-53 Revision 5 SI-10 Information Input Validation
[7] Standards Mapping - OWASP Application Security Verification Standard 4.0 1.5.4 Input and Output Architectural Requirements (L2 L3), 5.2.1 Sanitization and Sandboxing Requirements (L1 L2 L3), 5.3.1 Output Encoding and Injection Prevention Requirements (L1 L2 L3), 13.1.1 Generic Web Service Security Verification Requirements (L1 L2 L3), 14.4.2 HTTP Security Headers Requirements (L1 L2 L3), 14.4.4 HTTP Security Headers Requirements (L1 L2 L3)
[8] Standards Mapping - OWASP Mobile 2014 M1 Weak Server Side Controls
[9] Standards Mapping - OWASP Mobile 2024 M4 Insufficient Input/Output Validation
[10] Standards Mapping - OWASP Top 10 2004 A3 Broken Authentication and Session Management
[11] Standards Mapping - OWASP Top 10 2010 A6 Security Misconfiguration
[12] Standards Mapping - OWASP Top 10 2013 A2 Broken Authentication and Session Management
[13] Standards Mapping - OWASP Top 10 2017 A2 Broken Authentication
[14] Standards Mapping - OWASP Top 10 2021 A07 Identification and Authentication Failures
[15] Standards Mapping - Payment Card Industry Data Security Standard Version 1.1 Requirement 6.5.1
[16] Standards Mapping - Payment Card Industry Data Security Standard Version 2.0 Requirement 6.5.1
[17] Standards Mapping - Payment Card Industry Data Security Standard Version 3.0 Requirement 6.5.1
[18] Standards Mapping - Payment Card Industry Data Security Standard Version 3.1 Requirement 6.5.1
[19] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2 Requirement 6.5.1
[20] Standards Mapping - Payment Card Industry Data Security Standard Version 3.2.1 Requirement 6.5.1
[21] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0 Requirement 6.2.4
[22] Standards Mapping - Payment Card Industry Data Security Standard Version 4.0.1 Requirement 6.2.4
[23] Standards Mapping - Payment Card Industry Software Security Framework 1.0 Control Objective 4.2 - Critical Asset Protection
[24] 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
[25] 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
[26] Standards Mapping - SANS Top 25 2009 Insecure Interaction - CWE ID 116
[27] Standards Mapping - Security Technical Implementation Guide Version 3.1 APP3510 CAT I
[28] Standards Mapping - Security Technical Implementation Guide Version 3.4 APP3510 CAT I, APP3530 CAT II
[29] Standards Mapping - Security Technical Implementation Guide Version 3.5 APP3510 CAT I
[30] Standards Mapping - Security Technical Implementation Guide Version 3.6 APP3510 CAT I
[31] Standards Mapping - Security Technical Implementation Guide Version 3.7 APP3510 CAT I
[32] Standards Mapping - Security Technical Implementation Guide Version 3.9 APP3510 CAT I
[33] Standards Mapping - Security Technical Implementation Guide Version 3.10 APP3510 CAT I
[34] Standards Mapping - Security Technical Implementation Guide Version 4.2 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[35] Standards Mapping - Security Technical Implementation Guide Version 4.3 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[36] Standards Mapping - Security Technical Implementation Guide Version 4.4 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[37] Standards Mapping - Security Technical Implementation Guide Version 4.5 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[38] Standards Mapping - Security Technical Implementation Guide Version 4.6 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[39] Standards Mapping - Security Technical Implementation Guide Version 4.7 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[40] Standards Mapping - Security Technical Implementation Guide Version 4.8 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[41] Standards Mapping - Security Technical Implementation Guide Version 4.9 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[42] Standards Mapping - Security Technical Implementation Guide Version 4.10 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[43] Standards Mapping - Security Technical Implementation Guide Version 4.11 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[44] Standards Mapping - Security Technical Implementation Guide Version 4.1 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[45] Standards Mapping - Security Technical Implementation Guide Version 5.1 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[46] Standards Mapping - Security Technical Implementation Guide Version 5.2 APSC-DV-002520 CAT II, APSC-DV-002560 CAT I
[47] Standards Mapping - Security Technical Implementation Guide Version 5.3 APSC-DV-002520 CAT II, APSC-DV-002530 CAT II, APSC-DV-002560 CAT I
[48] Standards Mapping - Security Technical Implementation Guide Version 6.1 APSC-DV-002520 CAT II, APSC-DV-002530 CAT II, APSC-DV-002560 CAT I
[49] Standards Mapping - Web Application Security Consortium Version 2.00 Content Spoofing (WASC-12)
desc.dynamic.xtended_preview.setting_manipulation_character_set