CWE-484: Omitted Break Statement in Switch

Code Examples & CVEs

Demonstrative Examples

In both of these examples, a message is printed based on the month passed into the function:

Both examples do not use a break statement after each case, which leads to unintended fall-through behavior. For example, calling "printMessage(10)" will result in the text "OctoberNovemberDecember is a great month" being printed.

BadJava

public void printMessage(int month){                         switch (month) {                                                                 case 1: print("January");case 2: print("February");case 3: print("March");case 4: print("April");case 5: print("May");case 6: print("June");case 7: print("July");case 8: print("August");case 9: print("September");case 10: print("October");case 11: print("November");case 12: print("December");                            }println(" is a great month");                      }

In both of these examples, a message is printed based on the month passed into the function:

BadC

void printMessage(int month){                         switch (month) {                                                                 case 1: printf("January");case 2: printf("February");case 3: printf("March");case 4: printf("April");case 5: printff("May");case 6: printf("June");case 7: printf("July");case 8: printf("August");case 9: printf("September");case 10: printf("October");case 11: printf("November");case 12: printf("December");                            }printf(" is a great month");                      }

Source-backed guidance

Additional facts reviewed against primary or authoritative security sources.

Verify controls for CWE-484 with SSDF evidence

Use NIST SSDF verification and vulnerability-response practices to detect CWE-484, Omitted Break Statement in Switch, 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 Omitted Break Statement in Switch during Implementation

MITRE associates mitigation with Implementation; documented detection approaches include White Box, Black Box, and Automated Static Analysis; recorded impacts include Alter Execution Logic. Use these source-defined anchors to turn CWE-484 into implementation, review, and verification checks for the affected component.

CWE-484: Omitted Break Statement in Switch — MITRE CWE

Triage CWE-484 against known exploitation evidence

Use CISA's Known Exploited Vulnerabilities catalog to test whether a vulnerability mapped to CWE-484, Omitted Break Statement in Switch, 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-484

Apply MITRE's full root-cause mapping guidance when using CWE-484, Omitted Break Statement in Switch. 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-484 with root-cause mapping checks

Apply MITRE's root-cause mapping quick tips to CWE-484, Omitted Break Statement in Switch. 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-484: Omitted Break Statement in Switch?+

CWE-484: Omitted Break Statement in Switch is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The product omits a break statement within a switch or similar construct, causing code associated with multiple conditions to execute. This can cause problems when the programmer only intended to execute code associated with one condition. This can lead to critical code executing in situations where it should not.

What are the security consequences of Omitted Break Statement in Switch?+

If exploited, CWE-484 (Omitted Break Statement in Switch) it can compromise Other, leading to outcomes such as Alter Execution Logic.

How do you prevent or mitigate Omitted Break Statement in Switch?+

Recommended mitigations for CWE-484 include: Omitting a break statement so that one may fall through is often indistinguishable from an error, and therefore should be avoided. If you need to use fall-through capabilities, make sure that you have clearly documented this within the switch statement, and ensure that you have examined all the logical possibilities. The functionality of omitting a break statement could be clarified with an if statement. This method is much safer.

How is Omitted Break Statement in Switch detected?+

CWE-484 can be detected using White Box and Black Box. Combining automated tooling with manual review typically yields the best coverage.

Which programming languages are affected by Omitted Break Statement in Switch?+

CWE-484 commonly affects C, C++, Java, C#, PHP and 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-484 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-484: Omitted Break Statement in Switch

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Code Examples & CVEs

Demonstrative Examples

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Parent Weaknesses

Source-backed guidance

Verify controls for CWE-484 with SSDF evidence

Address Omitted Break Statement in Switch during Implementation

Triage CWE-484 against known exploitation evidence

Apply precise root-cause mapping to CWE-484

Validate CWE-484 with root-cause mapping checks

Frequently Asked Questions

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