Invalid permissions for temporary file

Docs > Datadog Security > Code Security > Static Code Analysis (SAST) > SAST Rules > Invalid permissions for temporary file

Metadata

ID: java-security/tempfile-permissions

Language: Java

Severity: Warning

Category: Security

CWE: 732

Description

Always explicitly set secure permissions on temporary files immediately after creation. This includes granting read and write access only to the owner, and disabling execute permissions unless explicitly required. For example, use tempFile.setReadable(true, true), tempFile.setWritable(true, true), and tempFile.setExecutable(false) to restrict access appropriately.

Avoid relying on default file permissions or omitting permission settings altogether, as this can lead to overly permissive access. By following these best practices, you minimize security risks associated with temporary files in your Java applications.

Non-Compliant Code Examples

import java.io.File;
import java.io.IOException;

public class SecureTempFileWithPermissionsExample {
    public static void main(String[] args) throws IOException {
        File tempFile = File.createTempFile("secure_tempfile_", ".tmp");
        tempFile.setReadable(true, true);
        tempFile.deleteOnExit();
        System.out.println("Temporary file created with secure permissions at: " 
            + tempFile.getAbsolutePath());
    }
}

import java.io.File;
import java.io.IOException;

public class SecureTempFileExample {
    public static void main(String[] args) throws IOException {
        File tempFile = File.createTempFile("tempfile_", ".tmp");
        tempFile.deleteOnExit();
        System.out.println("Temporary file created at: " + tempFile.getAbsolutePath());
    }
}

Compliant Code Examples

import java.io.File;
import java.io.IOException;

public class SecureTempFileWithPermissionsExample {
    public static void main(String[] args) throws IOException {
        File tempFile = File.createTempFile("secure_tempfile_", ".tmp");
        tempFile.setReadable(true, true);
        tempFile.setWritable(true, true);
        tempFile.setExecutable(false);
        tempFile.deleteOnExit();
        System.out.println("Temporary file created with secure permissions at: " 
            + tempFile.getAbsolutePath());
    }
}