Published:2017/09/11  Last Updated:2017/09/11

JVN#57205588
Installer of FENCE-Explorer may insecurely load Dynamic Link Libraries and invoke executable files

Overview

Installer of FENCE-Explorer may insecurely load Dynamic Link Libraries and invoke executable files.

Products Affected

  • FENCE-Explorer for Windows V8.4.1 and earlier

Description

FENCE-Explorer provided by FUJITSU BROAD SOLUTION & CONSULTING Inc. is a tool to view and edit a file in "FENCE Briefcase" which is created by FENCE-Pro and other FENCE series software.  Installer of FENCE-Explorer contains an issue with the search path for DLL/executable files, which may lead to insecurely loading Dynamic Link Libraries and invoking executable files (CWE-427).

Impact

Arbitrary code may be executed with the privilege of the user invoking the installer.

Solution

Use the latest installer
Use the latest installer according to the information provided by the developer.
Users who already have installed FENCE-Explorer do not need to re-install the application, because this issue affects the installer only.

Also note that a user who uses FENCE-Explorer with Portable Application is not affected by this vulnerability because in that case a user can specify a directory to place files before executing FENCE-Explorer.  However, the executable file itself contains a DLL preloading vulnerability, therefore a user should be careful not to place a suspicious file sent by the third party in the directory.

Vendor Status

Vendor Status Last Update Vendor Notes
FUJITSU LIMITED Vulnerable 2017/09/11
Vendor Link
FUJITSU BROAD SOLUTION & CONSULTING Inc. Installer of FENCE-Explorer may insecurely load Dynamic Link Libraries

References

  1. Japan Vulnerability Note JVNTA#91240916
    Insecure DLL Loading and Command Execution Issues on Many Windows Application Programs

JPCERT/CC Addendum

Vulnerability Analysis by JPCERT/CC

CVSS v3 CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Base Score: 7.8
Attack Vector(AV) Physical (P) Local (L) Adjacent (A) Network (N)
Attack Complexity(AC) High (H) Low (L)
Privileges Required(PR) High (H) Low (L) None (N)
User Interaction(UI) Required (R) None (N)
Scope(S) Unchanged (U) Changed (C)
Confidentiality Impact(C) None (N) Low (L) High (H)
Integrity Impact(I) None (N) Low (L) High (H)
Availability Impact(A) None (N) Low (L) High (H)
CVSS v2 AV:N/AC:M/Au:N/C:P/I:P/A:P
Base Score: 6.8
Access Vector(AV) Local (L) Adjacent Network (A) Network (N)
Access Complexity(AC) High (H) Medium (M) Low (L)
Authentication(Au) Multiple (M) Single (S) None (N)
Confidentiality Impact(C) None (N) Partial (P) Complete (C)
Integrity Impact(I) None (N) Partial (P) Complete (C)
Availability Impact(A) None (N) Partial (P) Complete (C)

Comment

This analysis assumes that the user is tricked into placing a malicious DLL file prepared by an attacker in a specific folder.

Credit

Eili Masami of Tachibana Lab. reported this vulnerability to IPA.
JPCERT/CC coordinated with the developer under Information Security Early Warning Partnership.

Other Information

JPCERT Alert
JPCERT Reports
CERT Advisory
CPNI Advisory
TRnotes
CVE CVE-2017-10855
JVN iPedia JVNDB-2017-000221