Publisure Hybrid - Multiple Vulnerabilities

2020-06-28
ID: 103076
CVE: None
Download vulnerable application: None
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# Exploit Title: [PUBLISURE : From 0 to local Administrator (3 vulns) exploit-chain]
# Google Dork: [N/A]
# Date: [05/09/2019]
# Exploit Author: [Bourbon Jean-Marie (@kmkz_security) - Hacknowledge company]
# Vendor Homepage: [https://www.publisure.com/]
# Software Link: [N/C]
# Version: [version 2.1.2]
# Tested on: [Windows 7 Enterprise]
# CVE : [CVE-2019-14252, CVE-2019-14253, CVE-2019-14254]

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# Improper Access Control 
#
# CVSSv3: 7.2 (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N)
# OVE ID:  OVE-20190724-0002
# CVE ID:  CVE-2019-14253
#
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# (Pre-Authenticated) Multiples SQL injection
#
# CVSSv3: 8.2 (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N)
# OVE ID:  OVE-20190724-0003
# CVE ID:  CVE-2019-14254
#
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# Unrestricted File Upload RCE
#
# CVSSv3: 9.1(CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H)
# OVE ID:  OVE-20190724-0004
# CVE ID:  CVE-2019-14252
#
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# Fixes:
# 	Upgrade to latest product version and/or contact support for patches
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I. PRODUCT

Publisure Hybrid mail is a highly efficient and cost effective alternative to traditional methods of producing and posting correspondence within an organization. 
The Publisure system can either be used for centralized, internal production within your existing facilities or alternatively, it can be implemented as a fully outsourced solution.

Note that this advisory is based on a version 2.1.2 which is a legacy version since a newer one was released.

II. ADVISORY

A combination of three different vulnerabilities permits an unauthenticated attacker to gain Administrator access on the server hosting Publisure application.

III. VULNERABILITIES DESCRIPTIONS

a) The first issue permits to bypass authentication mechanism allowing malicious person to perform query on PHP forms within the /AdminDir folder that should be restricted.
b) The second weakness is that SQL queries are not well sanitized resulting in multiple SQL injection in "userAccFunctions.php" functions.
Using this two steps, an attacker can access passwords and/or grant access to user account "user" in order to become "Administrator" (for example).

c) Once successfully authenticated as an administrator, he is able to inject PHP backdoor by using "adminCons.php" form.
    This backdoor will then be stored in E:\PUBLISURE\webservice\webpages\AdminDir\Templates\ folder even if removed from "adminCons.php" view (permitting to hide the malicious PHP file).

IV. PROOF OF CONCEPT

a) Access to AdminDir PHP scripts and database querying is possible whithout authentication (ex: http://192.168.13.37/AdminDir/editUser.php?id=2) 
b) Vulnerable URL example: http://192.168.13.37/AdminDir/editUser.php?id=sqli
"editUser.php" vulnerable code: $user = getUserDtails($_GET['id']);

"userAccFunctions.php" vulnerable code example:

function getUserDtails($id) {
	global $db;
	//The reseller_accounts table has been used to store department information since PDQit
	$Q = "SELECT a.username as username,a.contact_firstname,a.contact_lastname,a.email,r.company_name, a.enabled, a.record_id, a.password, a.unique_identifier, a.reseller_id, a.approval, a.resourceEditType, a.docView FROM accounts a, reseller_accounts r WHERE r.record_id = a.reseller_id AND a.record_id = $id";
	$R = $db->query($Q);
	return $R;
}

c) "adminCons.php" form permits to upload leading to RCE and allow attacker to hide malicious PHP code stored within "/AdminDir/Templates" folder (ex: http://192.168.13.37/AdminDir/Templates/tata.php?c=whoami) 
 

V. RECOMMENDATIONS

a) Restrict access to administrative (and other) folder when non authenticated.
b) Prepare SQL query before execution using PDO to escape injections.
c) Check file type on file upload forms to prevent PHP code upload instead of templates.

  
VI. TIMELINE
 
July 23th, 2019: Vulnerability identification
July 30th, 2019: First contact with the editor  (Publisure) and vulnerabilities acknowledgement
August 13th, 2019: Contact to vendor to ask for fix - no reply
September 04th, 2019: Vendor was informed 24h before public disclosure
September 05th, 2019: public disclosure after 45 days

VIII. LEGAL NOTICES
 
The information contained within this advisory is supplied "as-is" with no warranties or guarantees of fitness of use or otherwise.
I accept no responsibility for any damage caused by the use or misuse of this advisory.

The applied disclosure policy is based on US CERT Responsible Disclosure Policy - https://www.us-cert.gov/vulnerability-disclosure-policy
1-4-2 (www01)