Oracle PeopleSoft HCM 9.2 XXE Injection

Application: Oracle PeopleSoft Versions Affected: PeopleSoft HCM 9.2 on PeopleTools 8.55 Vendor URL: http://oracle.com Bug: XXE Reported: 23.12.2016 Vendor response: 24.12.2016 Date of Public Advisory: 18.04.2017 Reference: Oracle CPU April 2017 Author: Nadya Krivdyuk (ERPScan) ### Description #### 1. ADVISORY INFORMATION Title:[ERPSCAN-17-020] XXE VIA DOCTYPE in PeopleSoft PeopleSoftServiceListeningConnector Advisory ID: [ERPSCAN-17-020] Risk: high CVE: CVE-2017-3548 Advisory URL: https://erpscan.com/advisories/erpscan-17-020-xxe-via-doctype-peoplesoft/ Date published: 18.04.2017 Vendors contacted: Oracle #### 2. VULNERABILITY INFORMATION Class: XXE Impact: File disclosure, network discovery Remotely Exploitable: yes Locally Exploitable: no CVSS Information CVSS Base Score v3: 8.0 / 10 CVSS Base Vector: AV : Attack Vector (Related exploit range) Network (N) AC : Attack Complexity (Required attack complexity) High (H) PR : Privileges Required (Level of privileges needed to exploit) High (H) UI : User Interaction (Required user participation) None (N) S : Scope (Change in scope due to impact caused to components beyond the vulnerable component) Changed (C) C : Impact to Confidentiality High (H) I : Impact to Integrity High (H) A : Impact to Availability High (H) #### 3. VULNERABILITY DESCRIPTION A malicious user can modify an XML-based request to include XML content that is then parsed locally. #### 4. VULNERABLE PACKAGES PeopleSoft HCM 9.2 on PeopleTools 8.55 #### 5. SOLUTIONS AND WORKAROUNDS To correct this vulnerability, implement Oracle CPU April 2017 #### 6. AUTHOR Nadya Krivdyuk #### 7. TECHNICAL DESCRIPTION An attacker can use an XML external entity vulnerability to send specially crafted unauthorized XML requests, which will be processed by the XML parser. The attacker can use an XML external entity vulnerability for getting unauthorised access to the OS file system. #### PoC ``` POST /PSIGW/PeopleSoftServiceListeningConnector HTTP/1.1 Host: 172.16.2.91:8000 Content-type: text/xml <!DOCTYPE a PUBLIC "-//B/A/EN" "C:\windows"> ```