Siemens SICAM PAS Vulnerabilities (Update A)

OVERVIEW

This updated advisory is a follow-up to the original advisory titled ICSA-16-336-01 Siemens SICAM PAS Vulnerabilities that was published December 1, 2016, on the NCCIC/ICS-CERT web site.

Siemens has released an advisory to inform its users on how to mitigate vulnerabilities that affect SICAM PAS. Ilya Karpov and Dmitry Sklyarov of Positive Technologies and Sergey Temnikov and Vladimir Dashchenko of Kaspersky Lab coordinated these vulnerabilities directly with Siemens. Siemens has produced an update to mitigate some of these vulnerabilities.

Some of these vulnerabilities could be exploited remotely.

AFFECTED PRODUCTS

--------- Begin Update A Part 1 of 2 --------

The following SICAM PAS versions are affected:

• SICAM PAS: All versions prior to 8.09.

--------- End Update A Part 1 of 2 ----------

IMPACT

Successful exploitation of these vulnerabilities may allow an attacker to cause a denial-of-service condition or remotely exploit arbitrary code.

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.

BACKGROUND

Siemens is a multinational company headquartered in Munich, Germany.

The affected product, SICAM PAS, is energy automation software for operating electrical substations. According to Siemens, SICAM PAS is deployed across the Energy sector. Siemens estimates that this product is used worldwide.

VULNERABILITY CHARACTERIZATION

VULNERABILITY OVERVIEW

USE OF HARD-CODED CREDENTIALSa

A factory account with hard-coded passwords is present in the SICAM PAS installations. Attackers might gain privileged access to the database over Port 2638/TCP.

SICAM PAS Versions 8.00 and higher are not affected by this vulnerability.

CVE-2016-8567b has been assigned to this vulnerability. A CVSS v3 base score of 9.8 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).c

STORING PASSWORDS IN A RECOVERABLE FORMATd

An authenticated local attacker with certain privileges could possibly reconstruct the passwords of users for accessing the database.

SICAM PAS Versions 8.00 and higher are not affected by this vulnerability.

CVE-2016-8566e has been assigned to this vulnerability. A CVSS v3 base score of 7.8 has been calculated; the CVSS vector string is (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).f

FILES OR DIRECTORIES ACCESSIBLE TO EXTERNAL PARTIESg

A remote attacker could use specially crafted packets sent to Port 19235/TCP to upload, download, or delete files in certain parts of the file system.

CVE-2016-9156h has been assigned to this vulnerability. A CVSS v3 base score of 7.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L).i

WEAKNESSES THAT AFFECT MEMORYj

Specially crafted packets sent to port 19234/TCP could cause a denial of service condition and potentially lead to unauthenticated remote code execution.

CVE-2016-9157k has been assigned to this vulnerability. A CVSS v3 base score of 9.8 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).l

VULNERABILITY DETAILS

EXPLOITABILITY

Some of these vulnerabilities could be exploited remotely.

EXISTENCE OF EXPLOIT

No known public exploits specifically target these vulnerabilities.

DIFFICULTY

An attacker with low skill would be able to exploit these vulnerabilities.

MITIGATION

--------- Begin Update A Part 2 of 2 --------

SICAM PAS Versions 8.09 and higher fix all four vulnerabilities. Siemens recommends that users upgrade to the latest version. In order to receive the SICAM PAS V8.09 update, please contact the Siemens Energy Customer Support Center at [email protected].

--------- End Update A Part 2 of 2 ----------

Siemens strongly recommends users protect network access with appropriate mechanisms (e.g., firewalls, segmentation, VPN). Siemens also advises that users configure the operational environment according to Siemens’ Operational Guidelines for Industrial Security:

<https://www.siemens.com/cert/operational-guidelines-industrial-security&gt;

For more information on this vulnerability and more detailed mitigation instructions, please see Siemens Security Advisory SSA-946325 at the following location:

<http://www.siemens.com/cert/advisories&gt;

ICS-CERT recommends that users take defensive measures to minimize the risk of exploitation of these vulnerabilities. Specifically, users should:

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

ICS-CERT also provides a section for control systems security recommended practices on the ICS-CERT web page. Several recommended 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 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.

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.

• aCWE-798: Use of Hard-coded Credentials, https://cwe.mitre.org/data/definitions/798.html, web site last accessed December 01, 2016.
• bNVD, https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-8567, NIST uses this advisory to create the CVE web site report. This web site will be active sometime after publication of this advisory.
• cCVSS Calculator, https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, web site last accessed December 01, 2016.
• dCWE-257: Storing Passwords in a Recoverable Format, https://cwe.mitre.org/data/definitions/257.html, web site last accessed December 01, 2016.
• eNVD, https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-8566, NIST uses this advisory to create the CVE web site report. This web site will be active sometime after publication of this advisory.
• fCVSS Calculator, https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H, web site last accessed December 01, 2016.
• gCWE-552: Files or Directories Accessible to External Parties, https://cwe.mitre.org/data/definitions/552.html, web site last accessed December 01, 2016.
• hNVD, https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-9156, NIST uses this advisory to create the CVE web site report. This web site will be active sometime after publication of this advisory.
• iCVSS Calculator, https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L, web site last accessed December 01, 2016.
• jCWE-633: Weaknesses that Affect Memory, https://cwe.mitre.org/data/definitions/633.html, web site last accessed December 01, 2016.
• kNVD, https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-9157, NIST uses this advisory to create the CVE web site report. This web site will be active sometime after publication of this advisory.
• lCVSS Calculator, https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H, web site last accessed December 01, 2016.

Contact Information

For any questions related to this report, please contact the CISA at:

Email: [email protected]
Toll Free: 1-888-282-0870

For industrial control systems cybersecurity information: https://us-cert.cisa.gov/ics
or incident reporting: https://us-cert.cisa.gov/report

CISA continuously strives to improve its products and services. You can help by choosing one of the links below to provide feedback about this product.

This product is provided subject to this Notification and this Privacy & Use policy.

Please share your thoughts.

We recently updated our anonymous product survey; we’d welcome your feedback.