名稱: Signed to Unsigned Conversion Error
The product uses a signed primitive and performs a cast to an unsigned primitive, which can produce an unexpected value if the value of the signed primitive can not be represented using an unsigned primitive.
一般資訊
引入方式
Implementation : It is dangerous to rely on implicit casts between signed and unsigned numbers because the result can take on an unexpected value and violate assumptions made by the program.適用平台
程式語言
名稱： C (Undetermined)名稱： C++ (Undetermined)
常見後果
| 範圍 | 影響 | 可能性 |
|---|---|---|
| Integrity | Unexpected State, Modify Memory, Read Memory 注意：Conversion between signed and unsigned values can lead to a variety of errors, but from a security standpoint is most commonly associated with integer overflow and buffer overflow vulnerabilities. Often, functions will return negative values to indicate a failure. When the result of a function is to be used as a size parameter, using these negative return values can have unexpected results. For example, if negative size values are passed to the standard memory copy or allocation functions, they will be implicitly cast to a large unsigned value. This may lead to an exploitable buffer overflow or underflow condition. |
觀察到的案例
| 參考資料 | 描述 |
|---|---|
CVE-2025-27363 | Font rendering library does not properly handle assigning a signed short value to an unsigned long (CWE-195), leading to an integer wraparound (CWE-190), causing too small of a buffer (CWE-131), leading to an out-of-bounds write (CWE-787). |
CVE-2007-4268 | Chain: integer signedness error (CWE-195) passes signed comparison, leading to heap overflow (CWE-122) |
偵測方法
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.)有效性 : High
漏洞對應備注
理由說明 : 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.備註 : 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.
參考資料
REF-62
The Art of Software Security AssessmentMark Dowd, John McDonald, Justin Schuh.
REF-18
The CLASP Application Security ProcessSecure Software, Inc..
https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf
REF-1534
Automated Technical Debt Measure, Version 2OMG.
https://www.omg.org/spec/ATDM2/1.0/PDF
提交
| 名稱 | 機構 | 日期 | 發布日期 | Version |
|---|---|---|---|---|
| CLASP | Draft 3 |
修改記錄
| 名稱 | 機構 | 日期 | 備註 |
|---|---|---|---|
| CWE Content Team | MITRE | updated Applicable_Platforms, Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings | |
| CWE Content Team | MITRE | updated Demonstrative_Examples | |
| CWE Content Team | MITRE | updated Common_Consequences, Description, Other_Notes, Relationships | |
| CWE Content Team | MITRE | updated Demonstrative_Examples | |
| CWE Content Team | MITRE | updated Demonstrative_Examples | |
| CWE Content Team | MITRE | updated Relationships | |
| CWE Content Team | MITRE | updated Common_Consequences | |
| CWE Content Team | MITRE | updated Common_Consequences | |
| CWE Content Team | MITRE | updated Demonstrative_Examples, References, Relationships | |
| CWE Content Team | MITRE | updated Demonstrative_Examples, Description | |
| CWE Content Team | MITRE | updated Relationships, Taxonomy_Mappings | |
| CWE Content Team | MITRE | updated Relationships | |
| CWE Content Team | MITRE | updated Observed_Examples, Taxonomy_Mappings | |
| CWE Content Team | MITRE | updated Relationships | |
| CWE Content Team | MITRE | updated Relationships | |
| CWE Content Team | MITRE | updated Relationships | |
| CWE Content Team | MITRE | updated Relationships | |
| CWE Content Team | MITRE | updated Demonstrative_Examples, References | |
| CWE Content Team | MITRE | updated Description | |
| CWE Content Team | MITRE | updated Detection_Factors, Relationships | |
| CWE Content Team | MITRE | updated Mapping_Notes | |
| CWE Content Team | MITRE | updated Observed_Examples | |
| CWE Content Team | MITRE | updated Weakness_Ordinalities | |
| CWE Content Team | MITRE | updated Common_Consequences, Demonstrative_Examples, Description, Modes_of_Introduction, References |
