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Joomla! <= 4.1.0 (Tar.php) Zip Slip Vulnerability
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[-] Software Link:

http://www.joomla.org/


[-] Affected Versions:

Version 4.1.0 and prior versions.
Version 3.10.6 and prior versions.


[-] Vulnerability Description:

The vulnerability is located in the 
/libraries/vendor/joomla/archive/src/Tar.php script. Specifically, into 
the Joomla\Archive\Tar::extract() method:

113.      $this->getTarInfo($this->data);
114.
115.      for ($i = 0, $n = \count($this->metadata); $i < $n; $i++)
116.      {
117.        $type = strtolower($this->metadata[$i]['type']);
118.
119.        if ($type == 'file' || $type == 'unix file')
120.        {
121.          $buffer = $this->metadata[$i]['data'];
122.          $path   = Path::clean($destination . '/' . 
$this->metadata[$i]['name']);
123.
124.          // Make sure the destination folder exists
125.          if (!Folder::create(\dirname($path)))
126.          {
127.            throw new \RuntimeException('Unable to create destination 
folder ' . \dirname($path));
128.          }
129.
130.          if (!File::write($path, $buffer))
131.          {
132.            throw new \RuntimeException('Unable to write entry to file ' . 
$path);
133.          }
134.        }
135.      }

The vulnerability exists because the above code is using the filename 
within the Tar archive ($path variable created at line 122) to write the 
extracted file by using File::write() at line 130, without properly 
verifying the destination path. This could be exploited to carry out Zip 
Slip (or Path Traversal) attacks and write/overwrite arbitrary files, 
potentially resulting in execution of arbitrary PHP code or other 
dangerous impacts. In the Joomla! core, successful exploitation of this 
vulnerability would require administrator privileges. However, there 
could be third-party components using the 
Joomla\Archive\Archive::extract() method. In such cases, this might 
potentially be exploited also by unauthenticated attackers, depending on 
the context.



[-] Solution:

Upgrade to version 3.10.7, 4.1.1, or later.


[-] Disclosure Timeline:

[19/02/2021] - Vendor notified
[21/02/2021] - Vulnerability acknowledged by the vendor
[21/02/2021] - Vendor sent details about a proposed patch
[21/02/2021] - Sent feedback about the patch correctness
[29/03/2022] - Vendor update released
[29/03/2022] - Public disclosure


[-] CVE Reference:

The Common Vulnerabilities and Exposures project (cve.mitre.org)
has assigned the name CVE-2022-23793 to this vulnerability.


[-] Credits:

Vulnerability discovered by Egidio Romano.


[-] Other References:

https://developer.joomla.org/security-centre/870-20220301


[-] Original Advisory:

http://karmainsecurity.com/KIS-2022-05