CyberArk Enterprise Password Vault – XML External Entity (XXE) Injection

-----------Product description
The CyberArk Enterprise Password Vault is a privileged access security solution to store, monitor and rotate credentials. The main objective of the solution is protecting the privileged accounts that are used to administrate the systems of the organisations.

-----------Vulnerability description
This vulnerability allows remote attackers to disclose sensitive information or potentially bypass the authentication system.

-----------Vulnerability Details
# Exploit Title: XML External Entity (XXE) Injection in SAML authentication
# Affected Component: Password Vault Web Access (PVWA)
# Affected Version: <=10.7
# Vendor: CyberArk
# Vendor Homepage:
# Date: 18/12/2018
# CVSS Base Score: 7.5 (High)
# CVSS Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
# Exploit Author: Marcelo TorĂ¡n (Nixu Corporation)
# CVE: CVE-2019-7442

-----------Technical Description
It has been found that the XML parser of the SAML authentication system of the Password Vault Web Access (PVWA) is vulnerable to XML External Entity (XXE) attacks via a crafted DTD. No user interaction or privileges are required as the vulnerability is triggered in pre-authentication.
The vulnerable component is:
The vulnerable argument: SAMLResponse

18/12/2018 – Vulnerability discovered
10/01/2019 – Vendor notified
23/01/2019 – Vulnerability accepted
05/02/2019 – CVE number requested
05/02/2019 – CVE number assigned
19/02/2019 – Vendor released a patch
19/02/2019 – Advisory released

-----------Proof of Concept (PoC)