From 16d05c4ef7fe55b4b7042d4e690772cdbaa65bcc Mon Sep 17 00:00:00 2001 From: Jonathan Leitschuh Date: Fri, 4 Nov 2022 15:06:12 +0000 Subject: [PATCH] vuln-fix: Zip Slip Vulnerability This fixes a Zip-Slip vulnerability. This change does one of two things. This change either 1. Inserts a guard to protect against Zip Slip. OR 2. 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())`. For number 2, 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: High CVSSS: 7.4 Detection: CodeQL (https://codeql.github.com/codeql-query-help/java/java-zipslip/) & OpenRewrite (https://public.moderne.io/recipes/org.openrewrite.java.security.ZipSlip) Reported-by: Jonathan Leitschuh Signed-off-by: Jonathan Leitschuh Bug-tracker: https://github.com/JLLeitschuh/security-research/issues/16 Co-authored-by: Moderne --- core/src/main/java/org/yes/cart/utils/impl/ZipUtils.java | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/core/src/main/java/org/yes/cart/utils/impl/ZipUtils.java b/core/src/main/java/org/yes/cart/utils/impl/ZipUtils.java index aa2de5651f..7986e42564 100644 --- a/core/src/main/java/org/yes/cart/utils/impl/ZipUtils.java +++ b/core/src/main/java/org/yes/cart/utils/impl/ZipUtils.java @@ -82,7 +82,11 @@ private void unzipEntry(final ZipFile zipfile, final ZipArchiveEntry entry, fina return; } - File outputFile = new File(outputDir, entry.getName()); + File outputFile = new File(outputDir, entry.getName()); + + if (!outputFile.toPath().normalize().startsWith(outputDir.toPath().normalize())) { + throw new IOException("Bad zip entry"); + } if (!outputFile.getParentFile().exists()) { createDir(outputFile.getParentFile()); }