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Submitted URL:
https://snyk.io/vuln/SNYK-DOTNET-ELFINDERNETCORE-1313838
Effective URL:
https://security.snyk.io/vuln/SNYK-DOTNET-ELFINDERNETCORE-1313838
Submission: On June 29 via api (June 29th 2022, 11:15:31 am UTC) from NL — Scanned from NL

Form analysis
2 forms found in the DOM

<form id="mktoForm_1461" style="display: none; font-family: Helvetica, Arial, sans-serif; font-size: 13px; color: rgb(51, 51, 51); width: 1px;" novalidate="novalidate" class="mktoForm mktoHasWidth mktoLayoutLeft">
  <style type="text/css">
    .mktoForm .mktoButtonWrap.mktoSimple .mktoButton {
      color: #fff;
      border: 1px solid #75ae4c;
      padding: 0.4em 1em;
      font-size: 1em;
      background-color: #99c47c;
      background-image: -webkit-gradient(linear, left top, left bottom, from(#99c47c), to(#75ae4c));
      background-image: -webkit-linear-gradient(top, #99c47c, #75ae4c);
      background-image: -moz-linear-gradient(top, #99c47c, #75ae4c);
      background-image: linear-gradient(to bottom, #99c47c, #75ae4c);
    }

    .mktoForm .mktoButtonWrap.mktoSimple .mktoButton:hover {
      border: 1px solid #447f19;
    }

    .mktoForm .mktoButtonWrap.mktoSimple .mktoButton:focus {
      outline: none;
      border: 1px solid #447f19;
    }

    .mktoForm .mktoButtonWrap.mktoSimple .mktoButton:active {
      background-color: #75ae4c;
      background-image: -webkit-gradient(linear, left top, left bottom, from(#75ae4c), to(#99c47c));
      background-image: -webkit-linear-gradient(top, #75ae4c, #99c47c);
      background-image: -moz-linear-gradient(top, #75ae4c, #99c47c);
      background-image: linear-gradient(to bottom, #75ae4c, #99c47c);
    }
  </style>
  <div class="mktoButtonRow"><span class="mktoButtonWrap mktoSimple" style="margin-left: 120px;"><button type="submit" class="mktoButton">Submit</button></span></div><input type="hidden" name="formid" class="mktoField mktoFieldDescriptor"
    value="1461"><input type="hidden" name="munchkinId" class="mktoField mktoFieldDescriptor" value="677-THP-415">
</form>

<form style="display: none; font-family: Helvetica, Arial, sans-serif; font-size: 13px; color: rgb(51, 51, 51); visibility: hidden; position: absolute; top: -500px; left: -1000px; width: 1600px;" novalidate="novalidate"
  class="mktoForm mktoHasWidth mktoLayoutLeft"></form>

Text Content

About Snyk
1. Snyk Vulnerability Database
2. NuGet
3. elfinder.netcore

DIRECTORY TRAVERSAL AFFECTING ELFINDER.NETCORE OPEN THIS LINK IN A NEW TAB
PACKAGE, VERSIONS [0,]

--------------------------------------------------------------------------------

8.6
high

* EXPLOIT MATURITY

Mature

* ATTACK COMPLEXITY

Low

* CONFIDENTIALITY

High

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components
are vulnerable in your application, and suggest you quick fixes.

Test your applications

* SNYK-ID

SNYK-DOTNET-ELFINDERNETCORE-1313838

* PUBLISHED

20 Aug 2021

* DISCLOSED

20 Aug 2021

* CREDIT

Timo Müller

Report a new vulnerability Found a mistake?

INTRODUCED: 20 AUG 2021

CVE-2021-23428 Open this link in a new tab

CWE-22 Open this link in a new tab

First added by Snyk
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HOW TO FIX?

There is no fixed version for elFinder.NetCore.

OVERVIEW

elFinder.NetCore is a file manager for Web.

Affected versions of this package are vulnerable to Directory Traversal. The
Path.Combine(...) method is used to create an absolute file path. Due to missing
sanitation of the user input and a missing check of the generated path its
possible to escape the Files directory via path traversal

POC

* git clone https://github.com/gordon-matt/elFinder.NetCore.git
* cd ./elFinder.NetCore/elFinder.NetCore.Web/
* libman restore
* export ASPNETCORE_ENVIRONMENT=Development
* dotnet run
* go to https://localhost:5001/file-manager
Rightlick on one of the example files and click `Rename`. Rename the file to `../Mountains.jpg`
(This should result in a get request to the URL: https://localhost:5001/el-finder/file-system/connector?cmd=rename&name=..%2Fevil.jpg&target=v1_L01vdW50YWlucy5qcGc1&_=1624303958535)
* Due to the directory traversal vulnerability the file was stored outside of the `Files` directory, and inside the web server root dir `wwwroot`.

DETAILS

A Directory Traversal attack (also known as path traversal) aims to access files
and directories that are stored outside the intended folder. By manipulating
files with "dot-dot-slash (../)" sequences and its variations, or by using
absolute file paths, it may be possible to access arbitrary files and
directories stored on file system, including application source code,
configuration, and other critical system files.

Directory Traversal vulnerabilities can be generally divided into two types:

* Information Disclosure: Allows the attacker to gain information about the
folder structure or read the contents of sensitive files on the system.

st is a module for serving static files on web pages, and contains a
vulnerability of this type. In our example, we will serve files from the public
route.

If an attacker requests the following URL from our server, it will in turn leak
the sensitive private key of the root user.

curl http://localhost:8080/public/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/root/.ssh/id_rsa

Note %2e is the URL encoded version of . (dot).

* Writing arbitrary files: Allows the attacker to create or replace existing
files. This type of vulnerability is also known as Zip-Slip.

One way to achieve this is by using a malicious zip archive that holds path
traversal filenames. When each filename in the zip archive gets concatenated to
the target extraction folder, without validation, the final path ends up outside
of the target folder. If an executable or a configuration file is overwritten
with a file containing malicious code, the problem can turn into an arbitrary
code execution issue quite easily.

The following is an example of a zip archive with one benign file and one
malicious file. Extracting the malicious file will result in traversing out of
the target folder, ending up in /root/.ssh/ overwriting the authorized_keys
file:

2018-04-15 22:04:29 ..... 19 19 good.txt
2018-04-15 22:04:42 ..... 20 20 ../../../../../../root/.ssh/authorized_keys

REFERENCES

* elFinder.NetCore Repository
* GitHub Additional Information

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security.snyk.io Open in urlscan Pro 2a02:26f0:6c00:291::ecd Public Scan

Form analysis 2 forms found in the DOM

Text Content

security.snyk.io Open in urlscan Pro
2a02:26f0:6c00:291::ecd Public Scan

Form analysis
2 forms found in the DOM