Published:2021/01/12  Last Updated:2021/01/12

JVN#69635538
The installer of SKYSEA Client View may insecurely load Dynamic Link Libraries

Overview

The installer of SKYSEA Client View may insecurely load Dynamic Link Libraries.

Products Affected

  • SKYSEA Client View Ver.1.020.05b to Ver.16.001.01g

Description

SKYSEA Client View provided by Sky Co., LTD. is an Enterprise IT Asset Management Tool.
The installer of SKYSEA Client View contains an issue with the DLL search path, which may lead to insecurely loading Dynamic Link Libraries (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 installers provided by the developer.
Also when executing the installer, be sure to check there are no suspicious files in the directory where the installer resides.

Users who already have installed the software do not need to re-install, because this issue affects the installers only, i.e. when the product is installed and uninstalled.

In addition, Ver.13.000.10o and earlier are End-of-Support, thus the developer recommends users to upgrade the product to the latetst version.

References

  1. Japan Vulnerability Notes 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

shogo kumamaru of LAC Co.,Ltd 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-2021-20616
JVN iPedia JVNDB-2021-000003