I am facing path traversal vulnerability while analyzing code through checkmarx. I am fetching path with below code:
String path = System.getenv(variableName);
and "path" variable value is traversing through many functions and finally used in one function with below code snippet:
File file = new File(path);
Checkmarx is marking it as medium severity vulnerability.
Please help. How to resolve it to make it compatible with checkmarx?
Other answers that I believe Checkmarx will accept as sanitizers include Path.normalize:
import java.nio.file.*;
String path = System.getenv(variableName);
Path p = Paths.get(path);
Path normalizedPath = p.normalize();
path = new File(normalizedPath.toString());
or the FilenameUtils.normalize method:
import org.apache.commons.io.FilenameUtils;
String path = System.getenv(variableName);
File file = new File(FilenameUtils.normalize(path));
File, not a String, so it should be File file = new File(normalizedPath.toString());. Otherwise all else is fine :)You can generate canonicalized path by calling File.getCanonicalPath().
In your case:
String path = System.getenv(variableName);
path = new File(path).getCanonicalPath();
For more information read Java Doc
