What is CWE-1332: Improper Handling of Faults that Lead to Instruction Skips?+
CWE-1332: Improper Handling of Faults that Lead to Instruction Skips is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The device is missing or incorrectly implements circuitry or sensors that detect and mitigate the skipping of security-critical CPU instructions when they occur. The operating conditions of hardware may change in ways that cause unexpected behavior to occur, including the skipping of security-critical CPU instructions. Generally, this can occur due to electrical disturbances or when the device operates outside of its expected conditions. In practice, application code may contain conditional branches that are security-sensitive (e.g., accepting or rejecting a user-provided password). These conditional branches are typically implemented by a single conditional branch instruction in the program binary which, if skipped, may lead to effectively flipping the branch condition - i.e., causing the wrong security-sensitive branch to be taken. This affects processes such as firmware authentication, password verification, and other security-sensitive decision points. Attackers can use fault injection techniques to alter the operating conditions of hardware so that security-critical instructions are skipped more frequently or more reliably than they would in a "natural" setting.
What are the security consequences of Improper Handling of Faults that Lead to Instruction Skips?+
If exploited, CWE-1332 (Improper Handling of Faults that Lead to Instruction Skips) it can compromise Confidentiality, Integrity and Authentication, leading to outcomes such as Bypass Protection Mechanism, Alter Execution Logic and Unexpected State.
How do you prevent or mitigate Improper Handling of Faults that Lead to Instruction Skips?+
Recommended mitigations for CWE-1332 include: Design strategies for ensuring safe failure if inputs, such as Vcc, are modified out of acceptable ranges. Design strategies for ensuring safe behavior if instructions attempt to be skipped. Identify mission critical secrets that should be wiped if faulting is detected, and design a mechanism to do the deletion.
How is Improper Handling of Faults that Lead to Instruction Skips detected?+
CWE-1332 can be detected using Automated Static Analysis, Simulation / Emulation and Manual Analysis. Combining automated tooling with manual review typically yields the best coverage.
Which programming languages are affected by Improper Handling of Faults that Lead to Instruction Skips?+
CWE-1332 commonly affects Not Language-Specific. Note that weaknesses are often language-agnostic patterns, so secure coding practices apply broadly.
What are real-world examples of Improper Handling of Faults that Lead to Instruction Skips?+
MITRE documents real CVEs mapped to CWE-1332, including CVE-2019-15894. You can look up the full details of each CVE, including CVSS scores and remediation guidance, on our CVE Lookup tool.
What is the difference between a CWE and a CVE?+
A CWE (Common Weakness Enumeration) like CWE-1332 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.