vuln-fix: Temporary File Information Disclosure (#61)

This fixes temporary file information disclosure vulnerability due to the use
of the vulnerable `File.createTempFile()` method. The vulnerability is fixed by
using the `Files.createTempFile()` method which sets the correct posix permissions.

Weakness: CWE-377: Insecure Temporary File
Severity: Medium
CVSSS: 5.5
Detection: CodeQL & OpenRewrite (https://public.moderne.io/recipes/org.openrewrite.java.security.SecureTempFileCreation)

Reported-by: Jonathan Leitschuh <[email protected]>
Signed-off-by: Jonathan Leitschuh <[email protected]>

Bug-tracker: JLLeitschuh/security-research#18


Co-authored-by: Moderne <[email protected]>

Co-authored-by: Moderne <[email protected]>

src/main/java/com/github/davidmoten/rx/buffertofile/Options.java

@@ -2,6 +2,7 @@
 
 import java.io.File;
 import java.io.IOException;
+import java.nio.file.Files;
 
 import com.github.davidmoten.util.Preconditions;
 
@@ -170,12 +171,12 @@ private static class FileFactoryHolder {
 			@Override
 			public File call() {
 				try {
-					return File.createTempFile(DEFAULT_FILE_PREFIX, "");
+					return Files.createTempFile(DEFAULT_FILE_PREFIX, "").toFile();
 				} catch (IOException e) {
 					throw new RuntimeException(e);
 				}
 			}
 		};
 	}
 
-}
+}