CWE-758: Reliance on Undefined, Unspecified, or Implementation-Defined Behavior

ClassIncomplete

The product uses an API function, data structure, or other entity in a way that relies on properties that are not always guaranteed to hold for that entity.

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Extended Description

This can lead to resultant weaknesses when the required properties change, such as when the product is ported to a different platform or if an interaction error (CWE-435) occurs.

Technical Details

Structure
Simple

Applicable To

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Frequently Asked Questions

What is CWE-758: Reliance on Undefined, Unspecified, or Implementation-Defined Behavior?+

CWE-758: Reliance on Undefined, Unspecified, or Implementation-Defined Behavior is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The product uses an API function, data structure, or other entity in a way that relies on properties that are not always guaranteed to hold for that entity. This can lead to resultant weaknesses when the required properties change, such as when the product is ported to a different platform or if an interaction error (CWE-435) occurs.

What are the security consequences of Reliance on Undefined, Unspecified, or Implementation-Defined Behavior?+

If exploited, CWE-758 (Reliance on Undefined, Unspecified, or Implementation-Defined Behavior) it can compromise Other, leading to outcomes such as Other.

What are real-world examples of Reliance on Undefined, Unspecified, or Implementation-Defined Behavior?+

MITRE documents real CVEs mapped to CWE-758, including CVE-2006-1902. You can look up the full details of each CVE, including CVSS scores and remediation guidance, on our CVE Lookup tool.

What is the difference between a CWE and a CVE?+

A CWE (Common Weakness Enumeration) like CWE-758 describes a category of software weakness — the underlying flaw type. A CVE (Common Vulnerabilities and Exposures) identifies a specific, real-world vulnerability in a particular product. In short, a CWE is the kind of mistake, and a CVE is an instance of that mistake being found in software.

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CWE-758: Reliance on Undefined, Unspecified, or Implementation-Defined Behavior | CWE Lookup | InventiveHQ