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1. EXECUTIVE SUMMARY
- CVSS v3 7.4
- ATTENTION: Exploitable remotely
- Vendor: Siemens
- Equipment: Mendix SAML Module
- Vulnerability: Authentication Bypass by Capture-replay
2. RISK EVALUATION
Successful exploitation of this vulnerability could allow remote attackers to gain unauthenticated access to the application.
3. TECHNICAL DETAILS
3.1 AFFECTED PRODUCTS
Siemens reported this vulnerability affects the following versions of Mendix SAML Module, a SAML cloud authentication application:
- Mendix SAML Module (Mendix 7 compatible): All versions prior to V1.17.0
- Mendix SAML Module (Mendix 8 compatible): All versions prior to V2.3.0
- Mendix SAML Module (Mendix 9 compatible): All versions prior to V3.3.1
3.2 VULNERABILITY OVERVIEW
Affected versions of the module provide insufficient protection from packet capture replay. This could allow unauthorized remote attackers to bypass authentication and access the application.
- CRITICAL INFRASTRUCTURE SECTORS: Multiple
- COUNTRIES/AREAS DEPLOYED: Worldwide
- COMPANY HEADQUARTERS LOCATION: Germany
Siemens reported this vulnerability to CISA.
Siemens and Mendix recommend users update to the latest versions of the respective devices:
- Mendix SAML Module (Mendix 7 compatible): Update to version V1.17.0 or later
- Mendix SAML Module (Mendix 8 compatible): Update to version V2.3.0 or later
- Mendix SAML Module (Mendix 9 compatible): Update to version V3.3.1 or later
For applications upgraded to Mendix 9 from earlier Mendix versions, the issue has already been resolved in V3.3.0.
For compatibility reasons, fixed versions still contain this issue, but only when the not recommended, non-default configuration option ‘Allow Idp Initiated Authentication’ is enabled.
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. 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 this vulnerability. This vulnerability has a high attack complexity.
For any questions related to this report, please contact the CISA at:
Toll Free: 1-888-282-0870
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