From 457ce98e6b11355995bca2c5201793d380ad6c6a Mon Sep 17 00:00:00 2001 From: Jonathan Leitschuh Date: Wed, 21 Sep 2022 15:23:26 +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/com/izforge/izpack/util/FileUtil.java | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/izpack-tools/src/main/java/com/izforge/izpack/util/FileUtil.java b/izpack-tools/src/main/java/com/izforge/izpack/util/FileUtil.java index 8a9f0e5d24..5c611a13e5 100644 --- a/izpack-tools/src/main/java/com/izforge/izpack/util/FileUtil.java +++ b/izpack-tools/src/main/java/com/izforge/izpack/util/FileUtil.java @@ -243,7 +243,7 @@ public static String getRelativeFileName(File file, File basedir) throws IOExcep } String canonicalFilePath = file.getCanonicalPath(); String canonicalBaseDirPath = basedir.getCanonicalPath(); - if (canonicalFilePath.startsWith(canonicalBaseDirPath)) + if (file.getCanonicalFile().toPath().startsWith(canonicalBaseDirPath)) { int length = canonicalBaseDirPath.length(); if (length < canonicalFilePath.length())