CWE
Home > CWE List > CWE- Individual Dictionary Definition (1.0.1)  
Search by ID:

CWE-128: Wrap-around Error

Individual Definition in a New Window
Wrap-around Error
Status: Incomplete
Weakness ID: 128 (Weakness Base)
Description
Summary

Wrap around errors occur whenever a value is incremented past the maximum value for its type and therefore "wraps around" to a very small, negative, or undefined value.

Likelihood of Exploit

Medium

Weakness Ordinalities
Primary (where the weakness exists independent of other weaknesses)
Causal Nature
Explicit (an explicit weakness resulting from behavior of the developer)
Common Consequences
Availability

Wrap-around errors generally lead to undefined behavior, infinite loops, and therefore crashes.

Integrity

If the value in question is important to data (as opposed to flow), simple data corruption has occurred. Also, if the wrap around results in other conditions such as buffer overflows, further memory corruption may occur.

Access control (instruction processing): A wrap around can sometimes trigger buffer overflows which can be used to execute arbitrary code. This is usually outside the scope of a program's implicit security policy.

Potential Mitigations

Requirements specification: The choice could be made to use a language that is not susceptible to these issues.

Architecture and Design

Provide clear upper and lower bounds on the scale of any protocols designed.

Implementation

Place sanity checks on all incremented variables to ensure that they remain within reasonable bounds.

Background Details

Due to how addition is performed by computers, if a primitive is incremented past the maximum value possible for its storage space, the system will fail to recognize this, and therefore increment each bit as if it still had extra space. Because of how negative numbers are represented in binary, primitives interpreted as signed may "wrap" to very large negative values.

Relationships
NatureTypeIDNameView(s) this relationship pertains toView(s)
ChildOfWeakness ClassWeakness ClassWeakness Class119Failure to Constrain Operations within the Bounds of an Allocated Memory Buffer
Development Concepts (primary)699
Research Concepts (primary)1000
PeerOfWeakness BaseWeakness BaseWeakness Base190Integer Overflow (Wrap or Wraparound)
Research Concepts1000
Relationship Notes

The relationship between overflow and wrap-around needs to be examined more closely, since several entries (including CWE-190) are closely related.

Taxonomy Mappings
Mapped Taxonomy NameMapped Node Name
CLASPWrap-around error
Applicable Platforms
Languages
C (Often)
C++ (Often)
Time of Introduction
* Implementation
Related Attack Patterns
CAPEC-ID(CAPEC Version 1.1)Attack Pattern Name
92Forced Integer Overflow
Content History
Submissions
CLASP. (Externally Mined)
Modifications
CWE Content Team. MITRE. 2008-09-08. (Internal)
updated Applicable_Platforms, Background_Details, Common_Consequences, Relationships, Relationship_Notes, Taxonomy_Mappings, Weakness_Ordinalities
Page Last Updated: October 16, 2008