9.3 High
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:M/Au:N/C:C/I:C/A:C
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.9 High
AI Score
Confidence
High
0.013 Low
EPSS
Percentile
86.0%
--------- Begin Update A Part 1 of 3 ---------
--------- End Update A Part 1 of 3 ---------
Successful exploitation of this vulnerability could allow an attacker to gain full remote access to the HMI.
Siemens reports this vulnerability affects the following SINAMICS products with telnet enabled on SIMATIC comfort HMI Panels:
The Telnet service of the HMI Comfort Panels system component in affected SINAMICS products does not require authentication, which may allow a remote attacker to gain access to the device if the service is enabled. Telnet is disabled by default.
--------- Begin Update A Part 2 of 3 ---------
CVE-2020-15798 has been assigned to this vulnerability. A CVSS v3 base score of 8.1 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H).
--------- End Update A Part 2 of 3 ---------
Siemens reported this vulnerability to CISA.
---------Begin Update A Part 3 of 3 ---------
Only HMI image versions prior to v16 Update 3a are affected. Siemens recommends updating the following products to v16 Update 4 or later:
As only SIMATIC HMI image versions prior to v15 SP1 Update 6 are affected, update the HMI panel image as included in your installation of the following products to v15 SP1 Update 6 or later version.
--------- End Update A Part 3 of 3 ---------
Siemens has identified the following specific workarounds and mitigations users can apply to reduce the risk:
As a general security measure, Siemens strongly recommends users protect network access to devices with appropriate mechanisms. In order to operate the devices in a protected IT environment, Siemens recommends users configure the environment according to Siemensβ operational guidelines for industrial security, and follow the recommendations in the product manuals.
Additional information on industrial security by Siemens can be found at: <https://www.siemens.com/industrialsecurity>
For additional information see Siemens Security Advisory SSA-752103
For more details regarding the telnet authentication vulnerability in SIMATIC HMI Comfort Panels, refer to Siemens Security Advisory SSA-520004
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.cisa.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.cisa.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 this vulnerability. This vulnerability has a attack complexity.
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2020-15798
cert-portal.siemens.com/operational-guidelines-industrial-security.pdf
cert-portal.siemens.com/productcert/pdf/ssa-520004.pdf
cert-portal.siemens.com/productcert/pdf/ssa-752103.pdf
cwe.mitre.org/data/definitions/306.html
new.siemens.com/global/en/products/automation/topic-areas/industrial-security.html
public.govdelivery.com/accounts/USDHSCISA/subscriber/new?topic_id=USDHSCISA_138
support.industry.siemens.com/cs/ww/en/view/109746530/
support.industry.siemens.com/cs/ww/en/view/109751848/
support.industry.siemens.com/cs/ww/en/view/109763890/
twitter.com/CISAgov
twitter.com/intent/tweet?text=Siemens%20SINAMICS%20Medium%20Voltage%20Products%20Telnet%20%28Update%20A%29+https://www.cisa.gov/news-events/ics-advisories/icsa-21-131-13
us-cert.cisa.gov/ics
us-cert.cisa.gov/ics
us-cert.cisa.gov/ics/alerts/ICS-ALERT-10-301-01
us-cert.cisa.gov/ics/recommended-practices
us-cert.cisa.gov/ics/tips/ICS-TIP-12-146-01B
us-cert.cisa.gov/sites/default/files/recommended_practices/NCCIC_ICS-CERT_Defense_in_Depth_2016_S508C.pdf
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-21-131-13&title=Siemens%20SINAMICS%20Medium%20Voltage%20Products%20Telnet%20%28Update%20A%29
www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
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-21-131-13
www.oig.dhs.gov/
www.siemens.com/industrialsecurity
www.surveymonkey.com/r/CISA-cyber-survey?product=https://www.cisa.gov/news-events/ics-advisories/icsa-21-131-13
www.usa.gov/
www.whitehouse.gov/
www.youtube.com/@cisagov
mailto:?subject=Siemens%20SINAMICS%20Medium%20Voltage%20Products%20Telnet%20%28Update%20A%29&body=www.cisa.gov/news-events/ics-advisories/icsa-21-131-13
9.3 High
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
COMPLETE
Integrity Impact
COMPLETE
Availability Impact
COMPLETE
AV:N/AC:M/Au:N/C:C/I:C/A:C
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.9 High
AI Score
Confidence
High
0.013 Low
EPSS
Percentile
86.0%