CWE-457 詳細

The code uses a variable that has not been initialized, leading to unpredictable or unintended results.

背景の詳細

導入モード

Implementation : The presence of an uninitialized variable can sometimes indicate a typographic error in the code.
Implementation : In C, using an uninitialized char * in some string libraries will return incorrect results, as the libraries expect the null terminator to always be at the end of a string, even if the string is empty.

適用可能なプラットフォーム

言語

名前： C (Sometimes)
名前： C++ (Sometimes)
名前： Perl (Often)
名前： PHP (Often)
クラス： Not Language-Specific (Undetermined)

一般的な結果

観察された例

潜在的な緩和策

Phases : Implementation
Ensure that critical variables are initialized before first use [REF-1485].
Phases : Build and Compilation
Most compilers will complain about the use of uninitialized variables if warnings are turned on.
Phases : Implementation // Operation
When using a language that does not require explicit declaration of variables, run or compile the software in a mode that reports undeclared or unknown variables. This may indicate the presence of a typographic error in the variable's name.
Phases : Requirements
Choose a language that is not susceptible to these issues.
Phases : Architecture and Design
Mitigating technologies such as safe string libraries and container abstractions could be introduced.

検出方法

Fuzzing

Fuzz testing (fuzzing) is a powerful technique for generating large numbers of diverse inputs - either randomly or algorithmically - and dynamically invoking the code with those inputs. Even with random inputs, it is often capable of generating unexpected results such as crashes, memory corruption, or resource consumption. Fuzzing effectively produces repeatable test cases that clearly indicate bugs, which helps developers to diagnose the issues.
有効性 : High

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.)
有効性 : High

脆弱性マッピングノート

理由 : This CWE entry is at the Variant level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
コメント : 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.

参考文献

REF-18

The CLASP Application Security Process
Secure Software, Inc..
https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf

REF-436

Exploiting Uninitialized Data
mercy.
https://web.archive.org/web/20070403193636/http://www.felinemenace.org/~mercy/papers/UBehavior/UBehavior.zip

REF-437

MS08-014 : The Case of the Uninitialized Stack Variable Vulnerability
Microsoft Security Vulnerability Research & Defense.
https://msrc.microsoft.com/blog/2008/03/ms08-014-the-case-of-the-uninitialized-stack-variable-vulnerability/

REF-44

24 Deadly Sins of Software Security
Michael Howard, David LeBlanc, John Viega.

REF-62

The Art of Software Security Assessment
Mark Dowd, John McDonald, Justin Schuh.

REF-1485

D3FEND: D3-VI Variable Initialization
D3FEND.
https://d3fend.mitre.org/technique/d3f:VariableInitialization/

REF-1534

Automated Technical Debt Measure, Version 2
OMG.
https://www.omg.org/spec/ATDM2/1.0/PDF

登録情報

変更履歴