SSA-158827

Siemens Security Advisory by Siemens ProductCERT

SSA-158827: Denial-of-Service Vulnerability in Automation License Manager

Publication Date:	2021-08-10
Last Update:	2021-08-10
Current Version:	V1.0
CVSS v3.1 Base Score:	5.9

SUMMARY

A vulnerability was identified in the Automation License Manager software that could be triggered by sending specially crafted packets to port 4410/tcp of an affected system. This could cause a denial-of-service preventing legitimate users from using the system.

Siemens has released an update for the Automation License Manager 6 and recommends to update to the latest version. Siemens recommends specific countermeasures for products where updates are not, or not yet available.

AFFECTED PRODUCTS AND SOLUTION

Affected Product and Versions	Remediation
Automation License Manager 5: All versions	See recommendations from section Workarounds and Mitigations
Automation License Manager 6: All versions < V6.0 SP9 Update 2	Update to V6.0 SP9 Update 2 or later https://support.industry.siemens.com/cs/ww/en/view/114358/

WORKAROUNDS AND MITIGATIONS

Siemens has identified the following specific workarounds and mitigations that customers can apply to reduce the risk:

On the Automation License Manager settings menu disable “Allow Remote Connections”
If remote connections are needed, limit remote access to port 4410/tcp to trusted systems only

GENERAL SECURITY RECOMMENDATIONS

As a general security measure, Siemens strongly recommends to protect network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends to configure the environment according to Siemens’ operational guidelines for Industrial Security (Download: https://www.siemens.com/cert/operational-guidelines-industrial-security), and to follow the recommendations in the product manuals.

Additional information on Industrial Security by Siemens can be found at: https://www.siemens.com/industrialsecurity

PRODUCT DESCRIPTION

The Automation License Manager (ALM) centrally manages license keys for various Siemens software products. Software products requiring license keys automatically report this requirement to the ALM. When the ALM finds a valid license key for this software, the software can be used in conformity with the end user license agreement.

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-2021-25659

Sending specially crafted packets to port 4410/tcp of an affected system could lead to extensive memory being consumed and as such could cause a denial-of-service preventing legitimate users from using the system.

CVSS v3.1 Base Score	5.9
CVSS Vector	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C
CWE:	CWE-400: Uncontrolled Resource Consumption

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 (2021-08-10): Publication Date

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://new.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.

SSA-158827