File 0001-Fix-vulnerability-to-path-traversal-attack... of Package ark.13625

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File 0001-Fix-vulnerability-to-path-traversal-attacks.patch of Package ark.13625

From 0df592524fed305d6fbe74ddf8a196bc9ffdb92f Mon Sep 17 00:00:00 2001
From: Elvis Angelaccio <elvis.angelaccio@kde.org>
Date: Wed, 29 Jul 2020 23:45:30 +0200
Subject: [PATCH] Fix vulnerability to path traversal attacks

Ark was vulnerable to directory traversal attacks because of
missing validation of file paths in the archive.

More details about this attack are available at:
https://github.com/snyk/zip-slip-vulnerability

Job::onEntry() is the only place where we can safely check the path of
every entry in the archive. There shouldn't be a valid reason
to have a "../" in an archive path, so we can just play safe and abort
the LoadJob if we detect such an entry. This makes impossibile to
extract this kind of malicious archives and perform the attack.

Thanks to Albert Astals Cid for suggesting to use QDir::cleanPath()
so that we can still allow loading of legitimate archives that
contain "../" in their paths but still resolve inside the extraction folder.
---
 kerfuffle/jobs.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/kerfuffle/jobs.cpp b/kerfuffle/jobs.cpp
index fdaa4869..f73b56f8 100644
--- a/kerfuffle/jobs.cpp
+++ b/kerfuffle/jobs.cpp
@@ -180,6 +180,14 @@ void Job::onError(const QString & message, const QString & details)
 
 void Job::onEntry(Archive::Entry *entry)
 {
+    const QString entryFullPath = entry->fullPath();
+    if (QDir::cleanPath(entryFullPath).contains(QLatin1String("../"))) {
+        qCWarning(ARK) << "Possibly malicious archive. Detected entry that could lead to a directory traversal attack:" << entryFullPath;
+        onError(i18n("Could not load the archive because it contains ill-formed entries and might be a malicious archive."), QString());
+        onFinished(false);
+        return;
+    }
+
     emit newEntry(entry);
 }
 
-- 
2.28.0

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File 0001-Fix-vulnerability-to-path-traversal-attacks.patch of Package ark.13625

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