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1. EXECUTIVE SUMMARY
- CVSS v3 8.8
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: Siemens
- Equipment: Desigo PXM Devices
- Vulnerabilities: OS Command Injection, Exposure of Sensitive Information to an Unauthorized Actor, Cross-Site Scripting, Cross-Site Request Forgery, Improper Neutralization of Encoded URI Schemes in a Web Page, Execution with Unnecessary Privileges
2. RISK EVALUATION
Successful exploitation of these vulnerabilities could allow an attacker to potentially access sensitive information, execute arbitrary commands, cause a denial-of-service condition, or perform remote code execution.
3. TECHNICAL DETAILS
3.1 AFFECTED PRODUCTS
The following Desigo devices contain the affected webserver:
- Desigo PXM30-1: All versions prior to V02.20.126.11-41
- Desigo PXM30.E: All versions prior to V02.20.126.11-41
- Desigo PXM40-1: All versions prior to V02.20.126.11-41
- Desigo PXM40.E: All versions prior to V02.20.126.11-41
- Desigo PXM50-1: All versions prior to V02.20.126.11-41
- Desigo PXM50.E: All versions prior to V02.20.126.11-41
- PXG3.W100-1: All versions prior to V02.20.126.11-37
- PXG3.W100-2: All versions prior to V02.20.126.11-41
- PXG3.W200-1: All versions prior to V02.20.126.11-37
- PXG3.W200-2: All versions prior to V02.20.126.11-41
3.2 VULNERABILITY OVERVIEW
3.2.1 IMPROPER NEUTRALIZATION OF SPECIAL ELEMENTS USED IN AN OS COMMAND (’OS COMMAND INJECTION’) CWE-78
Siemens Desigo PXM Devices’ webserver is vulnerable to OS command injection. An improper neutralization of special elements used in an OS Command with root privileges during a restore operation exists; validation of file names included in the input package are missing. By restoring a specifically crafted package, a remote low-privileged attacker could execute arbitrary system commands with root privileges on the device, potentially leading to a full compromise.
Siemens Desigo PXM Devices’ webserver is vulnerable to exposure of sensitive information to an unauthorized actor. Endpoints of the “Operation” web application that interpret and execute Axon language queries allow file read access to the device file system with root privileges. By supplying specific input/output (I/O) related Axon queries, a remote low-privileged attacker could read sensitive files on the device.
Siemens Desigo PXM Devices’ webserver is vulnerable to a CSRF in endpoints of the “Operation” web application that interpret and execute Axon language queries, due to the missing validation of anti-CSRF tokens or other origin checks. By convincing a victim to click on a malicious link or visit a specifically crafted web page while logged-in to the device web application, a remote unauthenticated attacker could execute arbitrary Axon queries against the device.
- CRITICAL INFRASTRUCTURE SECTORS: Critical Manufacturing
- COUNTRIES/AREAS DEPLOYED: Worldwide
- COMPANY HEADQUARTERS LOCATION: Germany
Siemens reported these vulnerabilities to CISA.
Siemens has released updates for the affected products and recommends users update to the latest versions:
- Desigo PXM30-1: Update to V02.20.126.11-41 or later
- Desigo PXM30.E: Update to V02.20.126.11-41 or later
- Desigo PXM40-1: Update to V02.20.126.11-41 or later
- Desigo PXM40.E: Update to V02.20.126.11-41 or later
- Desigo PXM50-1: Update to V02.20.126.11-41 or later
- Desigo PXM50.E: Update to V02.20.126.11-41 or later
- PXG3.W100-1: Update to V02.20.126.11-37 or later
- PXG3.W100-2: Update to V02.20.126.11-41 or later
- PXG3.W200-1: Update to V02.20.126.11-37 or later
- PXG3.W200-2: Update to V02.20.126.11-41 or later
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.
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.
For any questions related to this report, please contact the CISA at:
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