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).
1. EXECUTIVE SUMMARY
- CVSS v3 6.6
- ATTENTION: Exploitable remotely
- Vendor: Siemens
- Equipment: RUGGEDCOM CROSSBOW
- Vulnerabilities: Missing Authorization
2. RISK EVALUATION
Successful exploitation of these vulnerabilities could allow authenticated remote attackers to perform unauthorized actions.
3. TECHNICAL DETAILS
3.1 AFFECTED PRODUCTS
The following software from Siemens is affected:
- Siemens RUGGEDCOM CROSSBOW: All versions prior to V5.2
3.2 VULNERABILITY OVERVIEW
3.2.1 MISSING AUTHORIZATION CWE-862
The client query handler of the affected application fails to check for proper permissions for specific write queries. This could allow an authenticated remote attacker to perform unauthorized actions.
CVE-2023-27309 has been assigned to this vulnerability. A CVSS v3 base score of 5.0 has been assigned; the CVSS vector string is (AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L).
3.2.2. MISSING AUTHORIZATION CWE-862
The client query handler of the affected application fails to check for proper permissions when assigning groups to user accounts. This could allow an authenticated remote attacker to assign administrative groups to otherwise non-privileged user accounts.
CVE-2023-27310 has been assigned to this vulnerability. A CVSS v3 base score of 6.6 has been assigned; the CVSS vector string is (AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H).
3.3 BACKGROUND
- CRITICAL INFRASTRUCTURE SECTORS: Multiple
- 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 workaround/mitigation users can apply to reduce risk:
- RUGGEDCOM CROSSBOW: Update to V5.2 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. Additional information on Siemens Industrial Security can be found here.
For more information, see the associated Siemens security advisory SSA-260625 in HTML and CSAF.
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability these vulnerabilities. Specifically, users should:
- Minimize network exposure for all control system devices and/or systems, and ensure they are not accessible from the Internet.
- Locate control system networks and remote devices behind firewalls and isolate them from business networks.
- When remote access is required, use secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as its 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 at cisa.gov/ics. 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.
Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov/ics 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.
No known public exploits specifically target these vulnerabilities. These vulnerabilities have a high attack complexity.