CWE-1339
Insufficient Precision or Accuracy of a Real Number
Draft
2021-07-20
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2025-12-11
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Notifications pour un CWE
Restez informé de toutes modifications pour un CWE spécifique.
Nom: Insufficient Precision or Accuracy of a Real Number
The product processes a real number with an implementation in which the number's representation does not preserve required accuracy and precision in its fractional part, causing an incorrect result.
Informations générales
Informations de base
There are three major ways to store real numbers in computers. Each method is described along with the limitations of how they store their numbers.Modes d'introduction
Implementation : This weakness is introduced when the developer picks a method to represent a real number. The weakness may only be visible with very specific numeric inputs.Plateformes applicables
Langue
Class: Not Language-Specific (Undetermined)Systèmes d’exploitation
Class: Not OS-Specific (Undetermined)Architectures
Class: Not Architecture-Specific (Undetermined)Technologies
Class: Not Technology-Specific (Undetermined)Conséquences courantes
| Portée | Impact | Probabilité |
|---|---|---|
| Availability | DoS: Crash, Exit, or Restart Note: This weakness will generally lead to undefined results and therefore crashes. In some implementations the program will halt if the weakness causes an overflow during a calculation. | |
| Integrity | Execute Unauthorized Code or Commands Note: The results of the math are not as expected. This could cause issues where a value would not be properly calculated and provide an incorrect answer. | |
| Confidentiality Availability Access Control | Read Application Data, Modify Application Data Note: This weakness can sometimes trigger buffer overflows which can be used to execute arbitrary code. This is usually outside the scope of a product's implicit security policy. |
Exemples observés
| Références | Description |
|---|---|
CVE-2018-16069 | Chain: series of floating-point precision errors (CWE-1339) in a web browser rendering engine causes out-of-bounds read (CWE-125), giving access to cross-origin data |
CVE-2017-7619 | Chain: rounding error in floating-point calculations (CWE-1339) in image processor leads to infinite loop (CWE-835) |
CVE-2021-29529 | Chain: machine-learning product can have a heap-based buffer overflow (CWE-122) when some integer-oriented bounds are calculated by using ceiling() and floor() on floating point values (CWE-1339) |
CVE-2008-2108 | Chain: insufficient precision (CWE-1339) in random-number generator causes some zero bits to be reliably generated, reducing the amount of entropy (CWE-331) |
CVE-2006-6499 | Chain: web browser crashes due to infinite loop - "bad looping logic [that relies on] floating point math [CWE-1339] to exit the loop [CWE-835]" |
Mesures d’atténuation potentielles
Phases : Implementation // Patching and MaintenanceThe developer or maintainer can move to a more accurate representation of real numbers. In extreme cases, the programmer can move to representations such as ratios of BigInts which can represent real numbers to extremely fine precision. The programmer can also use the concept of an Unum real. The memory and CPU tradeoffs of this change must be examined. Since floating point reals are used in many products and many locations, they are implemented in hardware and most format changes will cause the calculations to be moved into software resulting in slower products.
Méthodes de détection
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.)Notes de cartographie des vulnérabilités
Justification : 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.Commentaire : 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.
Références
REF-1186
Is COBOL holding you hostage with Math?https://medium.com/the-technical-archaeologist/is-cobol-holding-you-hostage-with-math-5498c0eb428b
REF-1187
Intermediate results and arithmetic precisionhttps://www.ibm.com/docs/en/cobol-zos/6.2?topic=appendixes-intermediate-results-arithmetic-precision
REF-1188
8.1.2. Arbitrary Precision Numbershttps://www.postgresql.org/docs/8.3/datatype-numeric.html#DATATYPE-NUMERIC-DECIMAL
REF-1189
Muller's Recurrencehttps://scipython.com/blog/mullers-recurrence/
REF-1190
An Improvement To Floating Point Numbershttps://hackaday.com/2015/10/22/an-improvement-to-floating-point-numbers/
REF-1191
HIGH PERFORMANCE COMPUTING: ARE WE JUST GETTING WRONG ANSWERS FASTER?https://www3.nd.edu/~markst/cast-award-speech.pdf
Soumission
| Nom | Organisation | Date | Date de publication | Version |
|---|---|---|---|---|
| CWE Content Team | MITRE | 4.5 |
Modifications
| Nom | Organisation | Date | Commentaire |
|---|---|---|---|
| CWE Content Team | MITRE | updated Demonstrative_Examples | |
| CWE Content Team | MITRE | updated Common_Consequences, Description, Potential_Mitigations | |
| CWE Content Team | MITRE | updated References, Relationships | |
| CWE Content Team | MITRE | updated Mapping_Notes | |
| CWE Content Team | MITRE | updated Demonstrative_Examples | |
| CWE Content Team | MITRE | updated Demonstrative_Examples | |
| CWE Content Team | MITRE | updated Detection_Factors, Weakness_Ordinalities |
