CWE-1235: Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations

Code Examples & CVEs

Demonstrative Examples

Java has a boxed primitive for each primitive type. A long can be represented with the boxed primitive Long. Issues arise where boxed primitives are used when not strictly necessary.

In the above loop, we see that the count variable is declared as a boxed primitive. This causes autoboxing on the line that increments. This causes execution to be magnitudes less performant (time and possibly space) than if the "long" primitive was used to declare the count variable, which can impact availability of a resource.

BadJava

Long count = 0L; 					 					for (long i = 0; i < Integer.MAX_VALUE; i++) { 					 						count += i; 						 					 					}

This code uses primitive long which fixes the issue.

GoodJava

long count = 0L; 					 					for (long i = 0; i < Integer.MAX_VALUE; i++) { 					 						count += i; 						 					 					}

Source-backed guidance

Additional facts reviewed against primary or authoritative security sources.

Verify controls for CWE-1235 with SSDF evidence

Use NIST SSDF verification and vulnerability-response practices to detect CWE-1235, Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations, throughout the product lifecycle. Derive review questions, static or dynamic checks, and negative tests from the CWE's causal behavior; define the components and lifecycle stages each check covers; and retain findings with enough evidence to distinguish the root cause from symptoms and impacts. Track escapes and false negatives, then improve the verification plan after every confirmed occurrence.

NIST SP 800-218 Secure Software Development Framework — National Institute of Standards and Technology

Address Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations during Implementation

MITRE associates mitigation with Implementation; documented detection approaches include Automated Static Analysis; recorded impacts include DoS: Resource Consumption (CPU), DoS: Resource Consumption (Memory), DoS: Resource Consumption (Other), and Reduce Performance. Use these source-defined anchors to turn CWE-1235 into implementation, review, and verification checks for the affected component.

CWE-1235: Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations — MITRE CWE

Triage CWE-1235 against known exploitation evidence

Use CISA's Known Exploited Vulnerabilities catalog to test whether a vulnerability mapped to CWE-1235, Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations, has evidence of exploitation in the wild. Confirm the CVE-to-CWE root-cause mapping independently before attaching the example, then capture the affected product, required action, and remediation deadline. A missing KEV match is not evidence that the weakness is unexploited, and a KEV entry must not be generalized to every occurrence of this CWE.

Known Exploited Vulnerabilities Catalog — Cybersecurity and Infrastructure Security Agency

Apply precise root-cause mapping to CWE-1235

Apply MITRE's full root-cause mapping guidance when using CWE-1235, Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations. Separate weakness language from attacker prerequisites and technical impact, check the entry's abstraction and vulnerability-mapping notes, and prefer the most specific Base or Variant supported by the evidence. Record the rejected alternatives and require an independent review before the mapping is used for remediation trends or program metrics.

CVE to CWE Root Cause Mapping Guidance — MITRE CWE

Validate CWE-1235 with root-cause mapping checks

Apply MITRE's root-cause mapping quick tips to CWE-1235, Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations. Confirm the finding describes the causal weakness rather than an impact or attack pattern, compare the abstraction and mapping notes with plausible alternatives, and have a second reviewer challenge the selection. Preserve the evidence and reasoning so recurring defects can be measured against one consistent identifier.

CVE to CWE Root Cause Mapping Quick Tips — MITRE CWE

Frequently Asked Questions

What is CWE-1235: Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations?+

CWE-1235: Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The code uses boxed primitives, which may introduce inefficiencies into performance-critical operations.

What are the security consequences of Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations?+

If exploited, CWE-1235 (Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations) it can compromise Availability, leading to outcomes such as DoS: Resource Consumption (CPU), DoS: Resource Consumption (Memory), DoS: Resource Consumption (Other) and Reduce Performance.

How do you prevent or mitigate Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations?+

Recommended mitigations for CWE-1235 include: Use of boxed primitives should be limited to certain situations such as when calling methods with typed parameters. They should not be used for scientific computing or other performance critical operations. They are only suited to support "impedance mismatch" between reference types and primitives. Examine the use of boxed primitives prior to use. Use SparseArrays or ArrayMap instead of HashMap to avoid performance overhead.

Which programming languages are affected by Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations?+

CWE-1235 commonly affects Java and C#. Note that weaknesses are often language-agnostic patterns, so secure coding practices apply broadly.

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

A CWE (Common Weakness Enumeration) like CWE-1235 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.

CWE-1235: Incorrect Use of Autoboxing and Unboxing for Performance Critical Operations

Technical Details

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