CWE-484: Omitted Break Statement in Switch
Official CWE-484 CWE context with Glexia analysis, remediation guidance, related CVEs, and ATT&CK context.
Glexia's Take
CWE-484: Omitted Break Statement in Switch
Omitted Break Statement in Switch represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Executive Impact
- Other: Alter Execution Logic: This weakness can cause unintended logic to be executed and other unexpected application behavior.
Developer Pattern
CWE-484 is the kind of defect developers can usually prevent with explicit validation, safer framework defaults, and tests that exercise hostile input or unsafe state transitions.
Confidence
high confidence from CWE-484, 4.20.
Official CWE Definition
CWE-484: Omitted Break Statement in Switch
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.
Developer And Remediation Guidance
How teams prevent and detect this weakness
Causes
- 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.
Remediation
- Implementation: 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.
- Implementation: The functionality of omitting a break statement could be clarified with an if statement. This method is much safer.
Detection
- White Box: Omission of a break statement might be intentional, in order to support fallthrough. Automated detection methods might therefore be erroneous. Semantic understanding of expected product behavior is required to interpret whether the code is correct.
- Black Box: Since this weakness is associated with a code construct, it would be indistinguishable from other errors that produce the same behavior.
- Automated Static Analysis: Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)
Mappings
Related CVEs, CWEs, and ATT&CK context
Related CWEs
ATT&CK Relevance
ATT&CK relevance is shown only when reviewed or responsibly inferred.