Improper Check or Handling of Exceptional Conditions

The product does not properly anticipate or handle exceptional conditions that rarely occur during normal operation of the product.


The following examples help to illustrate the nature of this weakness and describe methods or techniques which can be used to mitigate the risk.

Note that the examples here are by no means exhaustive and any given weakness may have many subtle varieties, each of which may require different detection methods or runtime controls.

Example One

Consider the following code segment:

char buf[10], cp_buf[10];
fgets(buf, 10, stdin);
strcpy(cp_buf, buf);

The programmer expects that when fgets() returns, buf will contain a null-terminated string of length 9 or less. But if an I/O error occurs, fgets() will not null-terminate buf. Furthermore, if the end of the file is reached before any characters are read, fgets() returns without writing anything to buf. In both of these situations, fgets() signals that something unusual has happened by returning NULL, but in this code, the warning will not be noticed. The lack of a null terminator in buf can result in a buffer overflow in the subsequent call to strcpy().

Example Two

The following method throws three types of exceptions.

public void doExchange() throws IOException, InvocationTargetException, SQLException {

While it might seem tidier to write

public void doExchange() throws Exception {

doing so hampers the caller's ability to understand and handle the exceptions that occur. Further, if a later revision of doExchange() introduces a new type of exception that should be treated differently than previous exceptions, there is no easy way to enforce this requirement.

See Also

Comprehensive Categorization: Improper Check or Handling of Exceptional Conditions

Weaknesses in this category are related to improper check or handling of exceptional conditions.

CISQ Quality Measures - Reliability

Weaknesses in this category are related to the CISQ Quality Measures for Reliability. Presence of these weaknesses could reduce the reliability of the software.

SEI CERT Oracle Secure Coding Standard for Java - Guidelines 07. Exceptional Behavior (ERR)

Weaknesses in this category are related to the rules and recommendations in the Exceptional Behavior (ERR) section of the SEI CERT Oracle Secure Coding Standard for Java.

Comprehensive CWE Dictionary

This view (slice) covers all the elements in CWE.

CISQ Data Protection Measures

This view outlines the SMM representation of the Automated Source Code Data Protection Measurement specifications, as identified by the Consortium for Information & So...

Research Concepts

This view is intended to facilitate research into weaknesses, including their inter-dependencies, and can be leveraged to systematically identify theoretical gaps with...

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