CWE-379 Detail

The product creates a temporary file in a directory whose permissions allow unintended actors to determine the file's existence or otherwise access that file.

On some operating systems, the fact that the temporary file exists may be apparent to any user with sufficient privileges to access that directory. Since the file is visible, the application that is using the temporary file could be known. If one has access to list the processes on the system, the attacker has gained information about what the user is doing at that time. By correlating this with the applications the user is running, an attacker could potentially discover what a user's actions are. From this, higher levels of security could be breached.

Modes Of Introduction

Implementation

Applicable Platforms

Language

Class: Not Language-Specific (Undetermined)

Common Consequences

Observed Examples

Potential Mitigations

Phases : Requirements
Many contemporary languages have functions which properly handle this condition. Older C temp file functions are especially susceptible.
Phases : Implementation
Try to store sensitive tempfiles in a directory which is not world readable -- i.e., per-user directories.
Phases : Implementation
Avoid using vulnerable temp file functions.

Detection Methods

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.)
Effectiveness : High

Vulnerability Mapping Notes

Justification : This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.
Comment : Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.

References

REF-18

The CLASP Application Security Process
Secure Software, Inc..
https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf

REF-62

The Art of Software Security Assessment
Mark Dowd, John McDonald, Justin Schuh.

Submission

Modifications