51 lines
1.7 KiB
Plaintext
51 lines
1.7 KiB
Plaintext
include::../description.adoc[]
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== Noncompliant Code Example
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----
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Enumeration<? extends ZipEntry> entries = zipFile.entries();
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while (entries.hasMoreElements()) {
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ZipEntry entry = entries.nextElement();
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File extractedFile = new File(toDir, entry.getName());
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FileOutputStream fos = new FileOutputStream(extractedFile); // Noncompliant; entry.getName() that was used to created "extractedFile" may be tainted with "../../../../../../../../tmp/evil.sh"
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InputStream input = zipFile.getInputStream(entry);
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IOUtils.copy(input, fos);
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}
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----
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== Compliant Solution
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----
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Enumeration<? extends ZipEntry> entries = zipFile.entries();
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while (entries.hasMoreElements()) {
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ZipEntry zipEntry = entries.nextElement();
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String fileName = zipEntry.getName();
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File extractedFile = new File(toDir, fileName);
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String canonicalDirPath = toDir.getCanonicalPath();
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String canonicalDestPath = extractedFile.getCanonicalPath();
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sanitizeAgainstZipFlipVulnerability(fileName, canonicalDestPath, canonicalDirPath); // Compliant
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FileOutputStream fos = new FileOutputStream(extractedFile);
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InputStream input = zipFile.getInputStream(entry);
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IOUtils.copy(input, fos);
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}
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public static void sanitizeAgainstZipFlipVulnerability(String fileName, String canonicalDestPath, String canonicalDirPath) throws ArchiverException {
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if (fileName.indexOf("..") != -1 && !canonicalDestPath.startsWith(canonicalDirPath + File.separator)) { // Sanitizer
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throw new ArchiverException("The file " + fileName + " is trying to leave the target output directory.");
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}
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}
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----
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include::../see.adoc[]
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ifdef::rspecator-view[]
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== Comments And Links
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(visible only on this page)
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include::../comments-and-links.adoc[]
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endif::rspecator-view[]
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