6.8 Medium
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:M/Au:N/C:P/I:P/A:P
8.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8 Medium
AI Score
Confidence
High
0.001 Low
EPSS
Percentile
44.0%
This updated advisory is a follow-up to the advisory update titled ICSA-16-327-02 Siemens SIMATIC CP 343-1/CP 443-1 Modules and SIMATIC S7-300/S7-400 CPUs (Update A) that was published March 21, 2017, on the ICS webpage.
Under certain conditions, an attacker could use these vulnerabilities to perform operations as an authenticated user.
Siemens reports that the vulnerabilities affect the following SIMATIC products:
--------- Begin Update B Part 1 of 2 ---------
--------- End Update B Part 1 of 2 ---------
The integrated web server at Port 80/TCP or Port 443/TCP of the affected devices could allow remote attackers to perform actions with the permissions of an authenticated user, provided the targeted user has an active session and is induced to trigger the malicious request.
CVE-2016-8673 has been assigned to this vulnerability. A CVSS v3 base score of 6.3 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L).
The integrated web server delivers cookies without the βsecureβ flag. Modern browsers interpreting the flag would mitigate potential data leakage in case of clear text transmission.
CVE-2016-8672 has been assigned to this vulnerability. A CVSS v3 base score of 4.0 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N).
Inverse Path auditors in collaboration with Airbus ICT Industrial Security team reported this to Siemens.
--------- Begin Update B Part 2 of 2 ---------
Artem Zinenko from Kaspersky Lab identified additional affected products.
--------- End Update B Part 2 of 2 ---------
Siemens provides firmware versions that fix the vulnerabilities and recommends that users update to the fixed versions:
SIMATIC CP 343-1 Advanced: Update to v3.0.53.
SIMATIC CP 443-1 Advanced: Update to v3.2.17.
For SIMATIC S7-300/S7-400 CPUs, Siemens recommends the following mitigations:
Siemens strongly recommends users protect network access to SIMATIC S7-300/S7-400 CPUs and to the web interface of SIMATIC CP 343-1 Advanced and CP 443-1 Advanced devices with appropriate mechanisms. Siemens also advises that users configure the protected operational environment according to Siemensβ Operational Guidelines for Industrial Security.
For more information on this vulnerability and more detailed mitigation instructions, please see Siemens Security Advisory SSA-603476 at the following location: http://www.siemens.com/cert/advisories
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Specifically, users should:
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 on us-cert.gov. 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 on the ICS webpage on us-cert.gov in the Technical Information Paper, ICS-TIP-12-146-01BβTargeted Cyber Intrusion Detection and Mitigation Strategies.
Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to CISA for tracking and correlation against other incidents.
No known public exploits specifically target these vulnerabilities.
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-8672
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-8673
www.siemens.com/cert/advisories
cwe.mitre.org/data/definitions/345.html
cwe.mitre.org/data/definitions/614.html
new.siemens.com/global/en/products/services/cert.html#SecurityPublications
public.govdelivery.com/accounts/USDHSCISA/subscriber/new?topic_id=USDHSCISA_138
support.industry.siemens.com/cs/ww/en/view/109742236
support.industry.siemens.com/cs/ww/en/view/109745388
twitter.com/CISAgov
twitter.com/intent/tweet?text=Siemens%20SIMATIC%20CP%20343-1/CP%20443-1%20Modules%20and%20SIMATIC%20S7-300/S7-400%20CPUs%20Vulnerabilities%20%28Update%20B%29+https://www.cisa.gov/news-events/ics-advisories/icsa-16-327-02
www.dhs.gov
www.dhs.gov/foia
www.dhs.gov/performance-financial-reports
www.facebook.com/CISA
www.facebook.com/sharer/sharer.php?u=https://www.cisa.gov/news-events/ics-advisories/icsa-16-327-02&title=Siemens%20SIMATIC%20CP%20343-1/CP%20443-1%20Modules%20and%20SIMATIC%20S7-300/S7-400%20CPUs%20Vulnerabilities%20%28Update%20B%29
www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N
www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
www.instagram.com/cisagov
www.linkedin.com/company/cybersecurity-and-infrastructure-security-agency
www.linkedin.com/sharing/share-offsite/?url=https://www.cisa.gov/news-events/ics-advisories/icsa-16-327-02
www.oig.dhs.gov/
www.siemens.com/cert/operational-guidelines-industrial-security
www.surveymonkey.com/r/CISA-cyber-survey?product=https://www.cisa.gov/news-events/ics-advisories/icsa-16-327-02
www.us-cert.gov/ics
www.us-cert.gov/ics
www.us-cert.gov/ics/alerts/ICS-ALERT-10-301-01
www.us-cert.gov/ics/recommended-practices
www.us-cert.gov/ics/tips/ICS-TIP-12-146-01B
www.us-cert.gov/sites/default/files/recommended_practices/NCCIC_ICS-CERT_Defense_in_Depth_2016_S508C.pdf
www.usa.gov/
www.whitehouse.gov/
www.youtube.com/@cisagov
mailto:?subject=Siemens%20SIMATIC%20CP%20343-1/CP%20443-1%20Modules%20and%20SIMATIC%20S7-300/S7-400%20CPUs%20Vulnerabilities%20%28Update%20B%29&body=www.cisa.gov/news-events/ics-advisories/icsa-16-327-02
6.8 Medium
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:M/Au:N/C:P/I:P/A:P
8.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8 Medium
AI Score
Confidence
High
0.001 Low
EPSS
Percentile
44.0%