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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 <Jonathan.Leitschuh@gmail.com> Signed-off-by: Jonathan Leitschuh <Jonathan.Leitschuh@gmail.com> Bug-tracker: JLLeitschuh/security-research#16 Co-authored-by: Moderne <team@moderne.io>
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src/main/java/org/yzr/utils/file/ZipUtil.java

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Original file line numberDiff line numberDiff line change
@@ -24,7 +24,10 @@ public static String unzip(String path) {
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File dir = new File(dirPath);
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dir.mkdirs();
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} else {
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File targetFile = new File(destDirPath + File.separator + entry.getName());
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File targetFile = new File(destDirPath, entry.getName());
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if (!targetFile.toPath().normalize().startsWith(destDirPath)) {
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throw new RuntimeException("Bad zip entry");
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}
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if (!targetFile.getParentFile().exists()) {
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targetFile.getParentFile().mkdirs();
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}

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