From 6a3751844dcf56fcd41254a4879b7a8d5c46f436 Mon Sep 17 00:00:00 2001 From: Jonathan Leitschuh Date: Mon, 8 Aug 2022 21:43:21 +0000 Subject: [PATCH] vuln-fix: Partial Path Traversal Vulnerability This fixes a partial path traversal vulnerability. Replaces `dir.getCanonicalPath().startsWith(parent.getCanonicalPath())`, which is vulnerable to partial path traversal attacks, with the more secure `dir.getCanonicalFile().toPath().startsWith(parent.getCanonicalFile().toPath())`. To demonstrate this vulnerability, consider `"/usr/outnot".startsWith("/usr/out")`. The check is bypassed although `/outnot` is not under the `/out` directory. It's important to understand that the terminating slash may be removed when using various `String` representations of the `File` object. For example, on Linux, `println(new File("/var"))` will print `/var`, but `println(new File("/var", "/")` will print `/var/`; however, `println(new File("/var", "/").getCanonicalPath())` will print `/var`. Weakness: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') Severity: Medium CVSSS: 6.1 Detection: CodeQL & OpenRewrite (https://public.moderne.io/recipes/org.openrewrite.java.security.PartialPathTraversalVulnerability) Reported-by: Jonathan Leitschuh Signed-off-by: Jonathan Leitschuh Bug-tracker: https://github.com/JLLeitschuh/security-research/issues/13 Co-authored-by: Moderne --- src/main/java/water/deploy/VM.java | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/main/java/water/deploy/VM.java b/src/main/java/water/deploy/VM.java index e012b3aad7..3492268c3a 100644 --- a/src/main/java/water/deploy/VM.java +++ b/src/main/java/water/deploy/VM.java @@ -267,7 +267,7 @@ static String command(String[] javaArgs, String[] nodeArgs) { for( String s : System.getProperty("java.class.path").split(File.pathSeparator) ) { cp += cp.length() != 0 ? ":" : ""; String path = new File(s).getCanonicalPath(); - if( path.startsWith(h2o) ) + if( new File(s).getCanonicalFile().toPath().startsWith(h2o) ) path = path.substring(h2o.length() + 1); cp += path.replace('\\', '/').replace(" ", "\\ "); }