Tên: Inappropriate Encoding for Output Context

The product uses or specifies an encoding when generating output to a downstream component, but the specified encoding is not the same as the encoding that is expected by the downstream component.

Thông tin chung

Các cách xuất hiện

Implementation

Nền tảng áp dụng

Ngôn ngữ

Lớp: Not Language-Specific (Undetermined)

Hậu quả phổ biến

Phạm vi	Tác động	Khả năng xảy ra
Integrity Confidentiality Availability	Modify Application Data, Execute Unauthorized Code or Commands Ghi chú: An attacker could modify the structure of the message or data being sent to the downstream component. When the wrong encoding is used - even if closely related - the downstream component could decode the data incorrectly and misinterpret the output. This can have security consequences when the provided boundaries between control and data are inadvertently broken, because the resulting data could introduce control characters or special elements that were not sent by the product. The resulting data could then be used to bypass protection mechanisms such as input validation, and enable injection attacks.

Ví dụ đã quan sát

Tài liệu tham khảo	Mô tả
CVE-2009-2814	Server does not properly handle requests that do not contain UTF-8 data; browser assumes UTF-8, allowing XSS.

Các biện pháp giảm thiểu tiềm năng

Phases : Implementation
Use context-aware encoding. That is, understand which encoding is being used by the downstream component, and ensure that this encoding is used. If an encoding can be specified, do so, instead of assuming that the default encoding is the same as the default being assumed by the downstream component.
Phases : Architecture and Design
Where possible, use communications protocols or data formats that provide strict boundaries between control and data. If this is not feasible, ensure that the protocols or formats allow the communicating components to explicitly state which encoding/decoding method is being used. Some template frameworks provide built-in support.
Phases : Architecture and Design

Phương pháp phát hiện

Automated Static Analysis

Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
Hiệu quả : High

Ghi chú ánh xạ lỗ hổng

Lý do : This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
Bình luận : Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

Mẫu tấn công liên quan

ID CAPEC	Tên mẫu tấn công
CAPEC-468	Generic Cross-Browser Cross-Domain Theft An attacker makes use of Cascading Style Sheets (CSS) injection to steal data cross domain from the victim's browser. The attack works by abusing the standards relating to loading of CSS: 1. Send cookies on any load of CSS (including cross-domain) 2. When parsing returned CSS ignore all data that does not make sense before a valid CSS descriptor is found by the CSS parser.

Tài liệu tham khảo

REF-709

XSS Attacks
Jeremiah Grossman, Robert "RSnake" Hansen, Petko "pdp" D. Petkov, Anton Rager, Seth Fogie.

REF-725

DOM based XSS Prevention Cheat Sheet
OWASP.
http://www.owasp.org/index.php/DOM_based_XSS_Prevention_Cheat_Sheet

REF-45

OWASP Enterprise Security API (ESAPI) Project
OWASP.
https://owasp.org/www-project-enterprise-security-api/

Gửi

Tên	Tổ chức	Ngày	Ngày phát hành	Version
CWE Content Team	MITRE	2011-03-24 +00:00	2011-03-30 +00:00	1.12

Sửa đổi

Tên	Tổ chức	Ngày	Bình luận
CWE Content Team	MITRE	2011-06-01 +00:00	updated Common_Consequences, Relationships, Taxonomy_Mappings
CWE Content Team	MITRE	2011-06-27 +00:00	updated Demonstrative_Examples, Related_Attack_Patterns, Relationships
CWE Content Team	MITRE	2012-05-11 +00:00	updated Potential_Mitigations, References, Relationships, Taxonomy_Mappings
CWE Content Team	MITRE	2017-11-08 +00:00	updated References, Taxonomy_Mappings
CWE Content Team	MITRE	2019-01-03 +00:00	updated Relationships, Taxonomy_Mappings
CWE Content Team	MITRE	2019-06-20 +00:00	updated Relationships
CWE Content Team	MITRE	2020-02-24 +00:00	updated Relationships
CWE Content Team	MITRE	2023-01-31 +00:00	updated Description
CWE Content Team	MITRE	2023-04-27 +00:00	updated Detection_Factors, References, Relationships
CWE Content Team	MITRE	2023-06-29 +00:00	updated Mapping_Notes
CWE Content Team	MITRE	2025-09-09 +00:00	updated References
CWE Content Team	MITRE	2025-12-11 +00:00	updated Time_of_Introduction, Weakness_Ordinalities
CWE Content Team	MITRE	2026-10-28 +00:00	updated Common_Consequences, Description

Chi tiết CWE-838

CWE-838