Pillar weakness
Incomplete
Log in
The product does not properly anticipate or handle exceptional conditions that rarely occur during normal operation of the product.
Last updated
CWE-703 (Improper Check or Handling of Exceptional Conditions) is a pillar-level software weakness catalogued by MITRE in the Common Weakness Enumeration (CWE). It describes a recurring type of mistake that can lead to exploitable security vulnerabilities.
136 recorded CVEs are caused by CWE-703 (Improper Check or Handling of Exceptional Conditions), including 3 in CISA's KEV (Known Exploited Vulnerabilities) catalog. KEVs are shown first. 15 new CWE-703 CVEs have been recorded so far in 2026 (27 in 2025).
Showing 12 of 136 recorded CWE-703 CVEs. Track new ones as they are published and get AI-written analysis and fixes.
Monitor CWE-703 vulnerabilitiesWhat can happen when CWE-703 is exploited.
Read Application Data, DoS: Crash, Exit, or Restart, Unexpected State
Affects: Confidentiality, Availability, Integrity
Typically introduced during these phases of the software lifecycle.
According to SOAR [REF-1479], the following detection techniques may be useful:
Effectiveness: High
According to SOAR [REF-1479], the following detection techniques may be useful:
Effectiveness: High
According to SOAR [REF-1479], the following detection techniques may be useful:
Effectiveness: SOAR Partial
According to SOAR [REF-1479], the following detection techniques may be useful:
Effectiveness: High
Illustrative examples from MITRE showing how the weakness appears in code.
Consider the following code segment:
Vulnerable example
char buf[10], cp_buf[10];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().
The following method throws three types of exceptions.
Safe example
public void doExchange() throws IOException, InvocationTargetException, SQLException {Vulnerable example
public void doExchange() throws Exception {Real CVEs that MITRE cites as examples of this weakness.
Common questions about CWE-703.
The product does not properly anticipate or handle exceptional conditions that rarely occur during normal operation of the product.
136 recorded CVEs are attributed to CWE-703, including CVE-2021-25370, CVE-2021-25372, CVE-2022-22265. 3 are listed in CISA's Known Exploited Vulnerabilities (KEV) catalog.
Dynamic Analysis with Manual Results Interpretation: According to SOAR [REF-1479], the following detection techniques may be useful:
Exploiting CWE-703 can lead to: Read Application Data, DoS: Crash, Exit, or Restart, Unexpected State.
Yes. 3 CWE-703 vulnerabilities are in CISA's KEV catalog of actively exploited flaws, out of 136 recorded CVEs.
Weakness data is sourced from the MITRE CWE catalog (v4.20). CVE associations are aggregated and kept current by RadicalNotion.AI.
Get alerted the moment a new CWE-703 vulnerability affects your stack, with AI-written analysis, severity context, and remediation guidance.