As of January 10, 2023, CISA will no longer be updating ICS security advisories for Siemens product vulnerabilities beyond the initial advisory. For the most up-to-date information on vulnerabilities in this advisory, please see Siemens’ ProductCERT Security Advisories (CERT Services | Services | Siemens Global). 

View CSAF

1. EXECUTIVE SUMMARY

CVSS v4 8.6
ATTENTION: Exploitable remotely/low attack complexity
Vendor: Siemens
Equipment: RUGGEDCOM RM1224, SCALANCE M-800 Family
Vulnerabilities: Uncontrolled Resource Consumption, Improper Input Validation, Exposure of Data Element to Wrong Session, Insertion of Sensitive Information into Log File

2. RISK EVALUATION

Successful exploitation of these vulnerabilities could allow an authenticated attacker to execute arbitrary code, escalate privilege, forge 2FA tokens of other users, or cause a denial-of-service condition.

3. TECHNICAL DETAILS

3.1 AFFECTED PRODUCTS

The following products of Siemens, are affected:

Siemens RUGGEDCOM RM1224 LTE(4G) EU (6GK6108-4AM00-2BA2): Versions prior to V8.1
Siemens RUGGEDCOM RM1224 LTE(4G) NAM (6GK6108-4AM00-2DA2): Versions prior to V8.1
Siemens SCALANCE M804PB (6GK5804-0AP00-2AA2): Versions prior to V8.1
Siemens SCALANCE M812-1 ADSL-Router family: Versions prior to V8.1
Siemens SCALANCE M816-1 ADSL-Router family: Versions prior to V8.1
Siemens SCALANCE M826-2 SHDSL-Router (6GK5826-2AB00-2AB2): Versions prior to V8.1
Siemens SCALANCE M874-2 (6GK5874-2AA00-2AA2): Versions prior to V8.1
Siemens SCALANCE M874-3 3G-Router (CN) (6GK5874-3AA00-2FA2): Versions prior to V8.1
Siemens SCALANCE M874-3 (6GK5874-3AA00-2AA2): Versions prior to V8.1
Siemens SCALANCE M876-3 (6GK5876-3AA02-2BA2): Versions prior to V8.1
Siemens SCALANCE M876-3 (ROK) (6GK5876-3AA02-2EA2): Versions prior to V8.1
Siemens SCALANCE M876-4 (6GK5876-4AA10-2BA2): Versions prior to V8.1
Siemens SCALANCE M876-4 (EU) (6GK5876-4AA00-2BA2): Versions prior to V8.1
Siemens SCALANCE M876-4 (NAM) (6GK5876-4AA00-2DA2): Versions prior to V8.1
Siemens SCALANCE MUM853-1 (A1) (6GK5853-2EA10-2AA1): Versions prior to V8.1
Siemens SCALANCE MUM853-1 (B1) (6GK5853-2EA10-2BA1): Versions prior to V8.1
Siemens SCALANCE MUM853-1 (EU) (6GK5853-2EA00-2DA1): Versions prior to V8.1
Siemens SCALANCE MUM856-1 (A1) (6GK5856-2EA10-3AA1): Versions prior to V8.1
Siemens SCALANCE MUM856-1 (B1) (6GK5856-2EA10-3BA1): Versions prior to V8.1
Siemens SCALANCE MUM856-1 (CN) (6GK5856-2EA00-3FA1): Versions prior to V8.1
Siemens SCALANCE MUM856-1 (EU) (6GK5856-2EA00-3DA1): Versions prior to V8.1
Siemens SCALANCE MUM856-1 (RoW) (6GK5856-2EA00-3AA1): Versions prior to V8.1
Siemens SCALANCE S615 EEC LAN-Router (6GK5615-0AA01-2AA2): Versions prior to V8.1
Siemens SCALANCE S615 LAN-Router (6GK5615-0AA00-2AA2): Versions prior to V8.1

3.2 Vulnerability Overview

3.2.1 UNCONTROLLED RESOURCE CONSUMPTION CWE-400

Affected devices do not properly validate the length of inputs when performing certain configuration changes in the web interface allowing an authenticated attacker to cause a denial-of-service condition. The device needs to be restarted for the web interface to become available again.

CVE-2023-44321 has been assigned to this vulnerability. A CVSS v3 base score of 2.7 has been assigned; the CVSS vector string is (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L).

A CVSS v4 score has also been calculated for CVE-2023-44321. A base score of 5.1 has been calculated; the CVSS vector string is (CVSS4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N).

3.2.2 IMPROPER INPUT VALIDATION CWE-20

Affected devices do not properly validate input in specific VPN configuration fields. This could allow an authenticated remote attacker to execute arbitrary code on the device.

CVE-2024-41976 has been assigned to this vulnerability. A CVSS v3 base score of 7.2 has been assigned; the CVSS vector string is (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H).

A CVSS v4 score has also been calculated for CVE-2024-41976. A base score of 8.6 has been calculated; the CVSS vector string is (CVSS4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N).

3.2.3 EXPOSURE OF DATA ELEMENT TO WRONG SESSION CWE-488

Affected devices do not properly enforce isolation between user sessions in their web server component. This could allow an authenticated remote attacker to escalate their privileges on the devices.

CVE-2024-41977 has been assigned to this vulnerability. A CVSS v3 base score of 7.1 has been assigned; the CVSS vector string is (CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H).

A CVSS v4 score has also been calculated for CVE-2024-41977. A base score of 7.3 has been calculated; the CVSS vector string is (CVSS4.0/AV:N/AC:H/AT:N/PR:L/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N).

3.2.4 INSERTION OF SENSITIVE INFORMATION INTO LOG FILE CWE-532

Affected devices insert sensitive information about the generation of 2FA tokens into log files. This could allow an authenticated remote attacker to forge 2FA tokens of other users.

CVE-2024-41978 has been assigned to this vulnerability. A CVSS v3 base score of 6.5 has been assigned; the CVSS vector string is (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N).

A CVSS v4 score has also been calculated for CVE-2024-41978. A base score of 7.1 has been calculated; the CVSS vector string is (CVSS4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N).

3.3 BACKGROUND

CRITICAL INFRASTRUCTURE SECTORS: Chemical, Energy, Food and Agriculture, Healthcare and Public Health, Transportation Systems, and Water and Wastewater Systems
COUNTRIES/AREAS DEPLOYED: Worldwide
COMPANY HEADQUARTERS LOCATION: Germany

3.4 RESEARCHER

Siemens reported these vulnerabilities to CISA.

4. MITIGATIONS

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

All affected products: Update to V8.1 or later version

As a general security measure, Siemens recommends protecting network access to devices with appropriate mechanisms. To operate the devices in a protected IT environment, Siemens recommends configuring the environment according to Siemens’ operational guidelines for industrial security and following recommendations in the product manuals.

Additional information on industrial security by Siemens can be found on the Siemens industrial security webpage

For more information see the associated Siemens security advisory SSA-087301 in HTML and CSAF.

CISA recommends users take defensive measures to minimize the risk of exploitation of these vulnerabilities, such as:

Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet.
Locate control system networks and remote devices behind firewalls and isolating them from business networks.
When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs). Recognize VPNs may have vulnerabilities, should be updated to the most recent version available, and are only as secure as the connected devices.

CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.

CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.

CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets.

Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov in the technical information paper, ICS-TIP-12-146-01B–Targeted Cyber Intrusion Detection and Mitigation Strategies.

Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents.

CISA also recommends users take the following measures to protect themselves from social engineering attacks:

Do not click web links or open attachments in unsolicited email messages.
Refer to Recognizing and Avoiding Email Scams for more information on avoiding email scams.
Refer to Avoiding Social Engineering and Phishing Attacks for more information on social engineering attacks.

No known public exploitation specifically targeting these vulnerabilities has been reported to CISA at this time.

5. UPDATE HISTORY

August 15, 2024: Initial Publication