CWE-1046: Creation of Immutable Text Using String Concatenation

Source-backed guidance

Additional facts reviewed against primary or authoritative security sources.

Detect imprecise mappings involving CWE-1046

Review mappings to CWE-1046, Creation of Immutable Text Using String Concatenation, with MITRE's mapping and navigation criteria. Flag any selection that points to a View or Category, remains at a higher abstraction than the available evidence supports, or ignores relevant parent, child, peer, and alternative entries. Treat those findings as mapping-quality defects, correct them before publication, and retain the comparison trail for repeatable audits.

CWE Mapping and Navigation Guidance — MITRE CWE

Prevent CWE-1046 through an SSDF control plan

Use NIST SSDF practices to make prevention of CWE-1046, Creation of Immutable Text Using String Concatenation, an explicit development outcome. Translate the CWE definition into security requirements and design constraints, choose safer implementation patterns and toolchain checks, and define acceptance evidence before release. Feed every confirmed occurrence back into the requirements, design review, and coding rules so the same root cause is removed across the product rather than patched in one location.

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

Triage CWE-1046 against known exploitation evidence

Use CISA's Known Exploited Vulnerabilities catalog to test whether a vulnerability mapped to CWE-1046, Creation of Immutable Text Using String Concatenation, 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

Use MITRE taxonomy anchors to review Creation of Immutable Text Using String Concatenation

Recorded impacts include Reduce Performance; related weaknesses include CWE-1176. Use these source-defined anchors to turn CWE-1046 into implementation, review, and verification checks for the affected component.

CWE-1046: Creation of Immutable Text Using String Concatenation — MITRE CWE

Validate CWE-1046 with root-cause mapping checks

Apply MITRE's root-cause mapping quick tips to CWE-1046, Creation of Immutable Text Using String Concatenation. 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-1046: Creation of Immutable Text Using String Concatenation?+

CWE-1046: Creation of Immutable Text Using String Concatenation is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The product creates an immutable text string using string concatenation operations. When building a string via a looping feature (e.g., a FOR or WHILE loop), the use of += to append to the existing string will result in the creation of a new object with each iteration, which can be inefficient in comparison with use of text buffer data elements.

What are the security consequences of Creation of Immutable Text Using String Concatenation?+

If exploited, CWE-1046 (Creation of Immutable Text Using String Concatenation) it can compromise Other, leading to outcomes such as Reduce Performance.

Which programming languages are affected by Creation of Immutable Text Using String Concatenation?+

CWE-1046 commonly affects Not Language-Specific. 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-1046 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-1046: Creation of Immutable Text Using String Concatenation

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