SSA-709003: Privilege Escalation Vulnerability in License Management Utility (LMU)
Publication Date:
2020-09-08
Last Update:
2020-09-08
Current Version:
V1.0
CVSS v3.1 Base Score:
7.8
SUMMARY
The latest update for the License Management Utility (LMU), which is used by multiple Siemens building technology products, fixes a vulnerability that could allow local users to escalate privileges and execute code as local SYSTEM user.
Siemens has released an update version of LMU, recommends to install this update on all affected systems and provides specific countermeasures for yet unpatched systems.
AFFECTED PRODUCTS AND SOLUTION
WORKAROUNDS AND MITIGATIONS
Siemens has identified the following specific workarounds and mitigations that customers can apply to reduce the risk:
Apply security hardening of the Windows Server, where LMU is installed on, in accordance with your corporate security policies or up-to-date hardening guidelines
Ensure that only trusted persons have access to the system and avoid the configuration of additional local accounts on the server
GENERAL SECURITY RECOMMENDATIONS
As a general security measure Siemens strongly recommends to protect network access to affected products with appropriate mechanisms. It is advised to follow recommended security practices in order to run the devices in a protected IT environment.
PRODUCT DESCRIPTION
License Management Utiliy (LMU) is the unified license management system for Siemens’ building automation products such as Desigo CC and ABT.
VULNERABILITY CLASSIFICATION
The vulnerability classification has been performed by using the CVSS scoring system in version 3.1
(CVSS v3.1) (https://www.first.org/cvss ). The CVSS environmental score is specific to the customer’s
environment and will impact the overall CVSS score. The environmental score should therefore be
individually defined by the customer to accomplish final scoring.
An additional classification has been performed using the CWE classification, a community-developed
list of common software security weaknesses. This serves as a common language and as a baseline for
weakness identification, mitigation, and prevention efforts. A detailed list of CWE classes can be found
at: https://cwe.mitre.org/ .
Vulnerability CVE-2020-10056
The lmgrd service of the affected application is executed with local SYSTEM privileges on the server while its configuration can be modified by local users.
The vulnerability could allow a local authenticated attacker to execute arbitrary commands on the server with local SYSTEM privileges.
CVSS v3.1 Base Score
7.8
CVSS Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C
CWE:
CWE-250: Execution with Unnecessary Privileges
ACKNOWLEDGMENTS
Siemens thanks the following parties for their efforts:
Bundesamt für Sicherheit in der Informationstechnik (BSI)
for reporting the vulnerability
ADDITIONAL INFORMATION
For further inquiries on security vulnerabilities in Siemens products and solutions, please contact the
Siemens ProductCERT:
https://www.siemens.com/cert/advisories
HISTORY DATA
V1.0 (2020-09-08): Publication Date
TERMS OF USE
Siemens Security Advisories are subject to the terms and conditions contained in Siemens’ underlying
license terms or other applicable agreements previously agreed to with Siemens (hereinafter "License
Terms"). To the extent applicable to information, software or documentation made available in or through
a Siemens Security Advisory, the Terms of Use of Siemens’ Global Website (https://www.siemens.com/terms_of_use , hereinafter "Terms of Use"), in particular Sections 8-10 of the Terms of Use, shall apply
additionally. In case of conflicts, the License Terms shall prevail over the Terms of Use.