CWE-839
Numeric Range Comparison Without Minimum Check
2011-03-30
00h00 +00:00
00h00 +00:00
特定のCWEの通知
特定のCWEの変更情報をいち早くお届けします。
名前: Numeric Range Comparison Without Minimum Check
The product checks a value to ensure that it is less than or equal to a maximum, but it does not also verify that the value is greater than or equal to the minimum.
一般情報
導入モード
Implementation : Some products use signed integers or floats even when their values are only expected to be positive or 0. An input validation check might assume that the value is positive, and only check for the maximum value.適用可能なプラットフォーム
言語
名前： C (Often)名前： C++ (Often)
一般的な結果
| スコープ | 影響 | 可能性 |
|---|---|---|
| Confidentiality Integrity | Modify Memory, Read Memory 注記：If a negative value is used to access memory, buffers, or other indexable structures, it could access memory outside the bounds of the buffer. | |
| Availability | DoS: Resource Consumption (Memory), DoS: Resource Consumption (Other) 注記：In some contexts, a negative value could lead to resource consumption, e.g., if the negative value is used for memory allocation. | |
| Integrity Confidentiality Availability | Modify Application Data, Execute Unauthorized Code or Commands 注記：An attacker could modify the structure of the message or data being sent to the downstream component, possibly injecting commands. | |
| Integrity | Varies by Context, Unexpected State 注記：The use of a negative number in a positive-only context could have security implications for other types of resources. For example, a shopping cart might check that the user is not requesting more than 10 items, but a request for -3 items could cause the application to calculate a negative price and credit the attacker's account. |
観察された例
| 参考文献 | 説明 |
|---|---|
CVE-2010-1866 | Chain: integer overflow (CWE-190) causes a negative signed value, which later bypasses a maximum-only check (CWE-839), leading to heap-based buffer overflow (CWE-122). |
CVE-2009-1099 | Chain: 16-bit counter can be interpreted as a negative value, compared to a 32-bit maximum value, leading to buffer under-write. |
CVE-2011-0521 | Chain: kernel's lack of a check for a negative value leads to memory corruption. |
CVE-2010-3704 | Chain: parser uses atoi() but does not check for a negative value, which can happen on some platforms, leading to buffer under-write. |
CVE-2010-2530 | Chain: Negative value stored in an int bypasses a size check and causes allocation of large amounts of memory. |
CVE-2009-3080 | Chain: negative offset value to IOCTL bypasses check for maximum index, then used as an array index for buffer under-read. |
CVE-2008-6393 | Chain: file transfer client performs signed comparison, leading to integer overflow and heap-based buffer overflow. |
CVE-2008-4558 | Chain: negative ID in media player bypasses check for maximum index, then used as an array index for buffer under-read. |
潜在的な緩和策
Phases : ImplementationIf the number to be used is always expected to be positive, change the variable type from signed to unsigned or size_t.
Phases : Implementation
If the number to be used could have a negative value based on the specification (thus requiring a signed value), but the number should only be positive to preserve code correctness, then include a check to ensure that the value is positive.
検出方法
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.)脆弱性マッピングノート
理由 : 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.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-62
The Art of Software Security AssessmentMark Dowd, John McDonald, Justin Schuh.
REF-62
The Art of Software Security AssessmentMark Dowd, John McDonald, Justin Schuh.
登録情報
| 名前 | 組織 | 日付 | リリース日 | Version |
|---|---|---|---|---|
| CWE Content Team | MITRE | 1.12 |
変更履歴
| 名前 | 組織 | 日付 | コメント |
|---|---|---|---|
| CWE Content Team | MITRE | updated Common_Consequences | |
| CWE Content Team | MITRE | updated Demonstrative_Examples, References, Relationships | |
| CWE Content Team | MITRE | updated Relationships | |
| CWE Content Team | MITRE | updated Description | |
| CWE Content Team | MITRE | updated Relationships | |
| CWE Content Team | MITRE | updated Alternate_Terms, Description | |
| CWE Content Team | MITRE | updated Relationships | |
| CWE Content Team | MITRE | updated Mapping_Notes | |
| CWE Content Team | MITRE | updated Observed_Examples | |
| CWE Content Team | MITRE | updated Demonstrative_Examples | |
| CWE Content Team | MITRE | updated Detection_Factors, Time_of_Introduction, Weakness_Ordinalities | |
| CWE Content Team | MITRE | updated Common_Consequences, Description, Modes_of_Introduction, Relationships |
