Siemens SIMATIC STEP 7 TIA Portal Vulnerabilities
Aleksandr Timorin from Positive Technologies has identified authentication vulnerabilities in the Siemens SIMATIC STEP 7 TIA Portal application. Siemens has produced a service pack that mitigates these vulnerabilities.
The following Siemens products are affected:
- SIMATIC STEP 7 TIA Portal: All versions prior to V13 SP1
A local user who is tricked into exploiting these vulnerabilities could possibly escalate privileges for an attacker. Impact to individual organizations depends on many factors that are unique to each organization. NCCIC/ICS-CERT recommends that organizations evaluate the impact of these vulnerabilities based on their operational environment, architecture, and product implementation.
Siemens is a multinational company headquartered in Munich, Germany.
The affected product, SIMATIC STEP 7 TIA Portal, is engineering software for SIMATIC products. This software is deployed across several sectors including Chemical, Energy, Food and Agriculture, and Water and Wastewater Systems. Siemens estimates that these products are used primarily in the United States and Europe with a small percentage in Asia.
WEAK PASSWORD HASHINGCWE-916: Use of Password Hash With Insufficient Computational Effort, http://cwe.mitre.org/data/definitions/916.html, web site last accessed February 17, 2015.
Device user passwords in TIA Portal project files are stored using a weak hashing algorithm. Attackers with read access to the project file could possibly reconstruct the passwords for device users.
CVE-2015-1355NVD, http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-1355, NIST uses this advisory to create the CVE web site report. This web site will be active sometime after publication of this advisory. has been assigned to this vulnerability. A CVSS v2 base score of 2.1 has been assigned; the CVSS vector string is (AV:L/AC:L/Au:N/C:P/I:N/A:N).CVSS Calculator, http://nvd.nist.gov/cvss.cfm?version=2&vector=AV:L/AC:L/Au:N/C:P/I:N/A:N, web site last accessed February 17, 2015.
PERMISSIONS, PRIVILEGES, AND ACCESS CONTROLSCWE-264: Permissions, Privileges, and Access Controls, http://cwe.mitre.org/data/definitions/264.html, web site last accessed February 17, 2015.
Privilege information for device users is stored unprotected in the TIA Portal project file. Attackers with access to the project file could possibly read and modify the permissions for device users in the project file. If unsuspecting users are tricked to download the manipulated project file to the device, the user permissions become active.
CVE-2015-1356NVD, http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-1356, NIST uses this advisory to create the CVE web site report. This web site will be active sometime after publication of this advisory. has been assigned to this vulnerability. A CVSS v2 base score of 2.6 has been assigned; the CVSS vector string is (AV:L/AC:H/Au:N/C:P/I:P/A:N).CVSS Calculator, http://nvd.nist.gov/cvss.cfm?version=2&vector=AV:L/AC:H/Au:N/C:P/I:P/A:N, web site last accessed February 17, 2015.
These vulnerabilities are not exploitable remotely without local user interaction.
EXISTENCE OF EXPLOIT
No known public exploits specifically target these vulnerabilities.
Crafting a working exploit for these vulnerabilities would be difficult. Social engineering is required to convince the user to accept the malformed file. Additional user interaction is needed to load the malformed file. This decreases the likelihood of a successful exploit.
Siemens provides Service Pack 1 for STEP 7 TIA Portal V13, which mitigates the vulnerabilities.
For more information on these vulnerabilities and detailed instructions, please see Siemens Security Advisory SSA-234789 at the following location:
ICS-CERT encourages asset owners to take additional defensive measures to protect against this and other cybersecurity risks.
- Minimize network exposure for all control system devices and/or systems, and ensure that they are not accessible from the Internet.
- Locate control system networks and remote devices behind firewalls, and isolate them from the business network.
- When remote access is required, use secure methods, such as Virtual Private Networks (VPNs), recognizing that VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize that VPN is only as secure as the connected devices.
ICS-CERT also provides a section for control systems security recommended practices on the ICS-CERT web page at: http://ics-cert.us-cert.gov/content/recommended-practices. Several recommended practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. ICS-CERT reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.
Additional mitigation guidance and recommended practices are publicly available in the ICS‑CERT Technical Information Paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies, that is available for download from the ICS-CERT web site (http://ics-cert.us-cert.gov/).
Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to ICS-CERT for tracking and correlation against other incidents.
In addition, ICS-CERT recommends that users take the following measures to protect themselves from social engineering attacks:
- Do not click web links or open unsolicited attachments in email messages.
- Refer to Recognizing and Avoiding Email ScamsRecognizing and Avoiding Email Scams, http://www.us-cert.gov/reading_room/emailscams_0905.pdf, web site last accessed February 17, 2015. for more information on avoiding email scams.
- Refer to Avoiding Social Engineering and Phishing AttacksNational Cyber Alert System Cyber Security Tip ST04-014, http://www.us-cert.gov/cas/tips/ST04-014.html, web site last accessed February 17, 2015. for more information on social engineering attacks.