CWE-67: Improper Handling of Windows Device Names

VariantIncompleteExploit Likelihood: High

The product constructs pathnames from user input, but it does not handle or incorrectly handles a pathname containing a Windows device name such as AUX or CON. This typically leads to denial of service or an information exposure when the application attempts to process the pathname as a regular file.

View on MITRE

Extended Description

Not properly handling virtual filenames (e.g. AUX, CON, PRN, COM1, LPT1) can result in different types of vulnerabilities. In some cases an attacker can request a device via injection of a virtual filename in a URL, which may cause an error that leads to a denial of service or an error page that reveals sensitive information. A product that allows device names to bypass filtering runs the risk of an attacker injecting malicious code in a file with the name of a device.

Source-backed guidance

Additional facts reviewed against primary or authoritative security sources.

Verify controls for CWE-67 with SSDF evidence

Use NIST SSDF verification and vulnerability-response practices to detect CWE-67, Improper Handling of Windows Device Names, 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 Improper Handling of Windows Device Names during Implementation

MITRE associates mitigation with Implementation; recorded impacts include DoS: Crash, Exit, or Restart, Read Application Data, and Other; observed examples include CVE-2002-0106, CVE-2002-0200, and CVE-2002-1052. Use these source-defined anchors to turn CWE-67 into implementation, review, and verification checks for the affected component.

CWE-67: Improper Handling of Windows Device Names — MITRE CWE

Triage CWE-67 against known exploitation evidence

Use CISA's Known Exploited Vulnerabilities catalog to test whether a vulnerability mapped to CWE-67, Improper Handling of Windows Device Names, 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-67

Apply MITRE's full root-cause mapping guidance when using CWE-67, Improper Handling of Windows Device Names. 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-67 with root-cause mapping checks

Apply MITRE's root-cause mapping quick tips to CWE-67, Improper Handling of Windows Device Names. 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-67: Improper Handling of Windows Device Names?+

CWE-67: Improper Handling of Windows Device Names is a Common Weakness Enumeration (CWE) entry maintained by MITRE. The product constructs pathnames from user input, but it does not handle or incorrectly handles a pathname containing a Windows device name such as AUX or CON. This typically leads to denial of service or an information exposure when the application attempts to process the pathname as a regular file. Not properly handling virtual filenames (e.g. AUX, CON, PRN, COM1, LPT1) can result in different types of vulnerabilities. In some cases an attacker can request a device via injection of a virtual filename in a URL, which may cause an error that leads to a denial of service or an error page that reveals sensitive information. A product that allows device names to bypass filtering runs the risk of an attacker injecting malicious code in a file with the name of a device.

What are the security consequences of Improper Handling of Windows Device Names?+

If exploited, CWE-67 (Improper Handling of Windows Device Names) it can compromise Availability, Confidentiality and Other, leading to outcomes such as DoS: Crash, Exit, or Restart, Read Application Data and Other.

How do you prevent or mitigate Improper Handling of Windows Device Names?+

Recommended mitigations for CWE-67 include: Be familiar with the device names in the operating system where your system is deployed. Check input for these device names.

Which programming languages are affected by Improper Handling of Windows Device Names?+

CWE-67 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 Windows Device Names?+

MITRE documents real CVEs mapped to CWE-67, including CVE-2002-0106, CVE-2002-0200, CVE-2002-1052, CVE-2001-0493 and CVE-2001-0558. 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-67 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-67: Improper Handling of Windows Device Names

Extended Description

Technical Details

Applicable To

Security Consequences

Scope

Impact

Mitigation Strategies

Phase

Description

Detection Methods

Code Examples & CVEs

Observed CVE Examples (9)

CWE Relationships

Parent Weaknesses