4.3 Medium
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:M/Au:N/C:N/I:P/A:N
5.4 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
LOW
Integrity Impact
LOW
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
5.3 Medium
AI Score
Confidence
High
0.001 Low
EPSS
Percentile
36.3%
This updated advisory is a follow-up to the advisory update titled ICSA-20-042-07 Siemens SCALANCE X Switches (Update B) that was published April 13, 2021, to the ICS webpage on us-cert.cisa.gov.
Successful exploitation of this vulnerability could allow an attacker to perform administrative actions.
The following versions of SCALANCE X Switches, used to connect industrial components, are affected:
--------- Begin Update C Part 1 of 2 ---------
--------- End Update C Part 1 of 2 ---------
The device does not send the X-Frame-Option header in the administrative web interface, which makes it vulnerable to click-jacking attacks.
CVE-2019-13924 has been assigned to this vulnerability. A CVSS v3 base score of 4.2 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:L).
Siemens reported this vulnerability to CISA.
Siemens has released updates, which are recommended to be applied when possible:
--------- Begin Update C Part 2 of 2 ---------
--------- End Update C Part 2 of 2 ---------
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 more information see Siemens security advisory SSA-951513
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
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-13924
cert-portal.siemens.com/operational-guidelines-industrial-security.pdf
cert-portal.siemens.com/productcert/pdf/ssa-951513.pdf
cwe.mitre.org/data/definitions/693.html
public.govdelivery.com/accounts/USDHSCISA/subscriber/new?topic_id=USDHSCISA_138
support.industry.siemens.com/cs/document/109773547
support.industry.siemens.com/cs/document/62564534
support.industry.siemens.com/cs/ww/en/view/109756957/
support.industry.siemens.com/cs/ww/en/view/109756957/
support.industry.siemens.com/cs/ww/en/view/109756957/
support.industry.siemens.com/cs/ww/en/view/109756957/
support.industry.siemens.com/cs/ww/en/view/109792534/
support.industry.siemens.com/cs/ww/en/view/109814809/
twitter.com/CISAgov
twitter.com/intent/tweet?text=Siemens%20SCALANCE%20X%20Switches%20%28Update%20C%29+https://www.cisa.gov/news-events/ics-advisories/icsa-20-042-07
us-cert.cisa.gov/ics
us-cert.cisa.gov/ics
us-cert.cisa.gov/ics/recommended-practices
us-cert.cisa.gov/ics/tips/ICS-TIP-12-146-01B
us-cert.cisa.gov/ncas/tips/ST04-014
us-cert.cisa.gov/sites/default/files/publications/emailscams_0905.pdf
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
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www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:L
www.instagram.com/cisagov
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www.linkedin.com/sharing/share-offsite/?url=https://www.cisa.gov/news-events/ics-advisories/icsa-20-042-07
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-20-042-07
www.usa.gov/
www.whitehouse.gov/
www.youtube.com/@cisagov
mailto:?subject=Siemens%20SCALANCE%20X%20Switches%20%28Update%20C%29&body=www.cisa.gov/news-events/ics-advisories/icsa-20-042-07
4.3 Medium
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
PARTIAL
Availability Impact
NONE
AV:N/AC:M/Au:N/C:N/I:P/A:N
5.4 Medium
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
LOW
Integrity Impact
LOW
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
5.3 Medium
AI Score
Confidence
High
0.001 Low
EPSS
Percentile
36.3%