CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:M/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
Percentile
55.2%
Successful exploitation of this vulnerability could allow an unauthenticated remote attacker to cause interruptions in the network.
The following versions of SCALANCE X industrial switches are affected:
The OSPF protocol implementation in affected devices fails to verify the checksum and length fields in the OSPF LS update messages. Successful exploitation requires OSPF to be enabled on an affected device and could allow an unauthenticated remote attacker to cause network interruptions.
CVE-2021-37182 has been assigned to this vulnerability. A CVSS v3 base score of 5.9 has been calculated; the CVSS vector string is (AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H).
Siemens reported this vulnerability to CISA.
For all affected products, Siemens recommends updating to [v6.5 or later](<https://support.industry.siemens.com/cs/ww/en/ view/109809635/>).
Siemens has identified the following specific workarounds and mitigations users can apply to reduce the risk:
As a general security measure, Siemens recommends protecting network access to devices with appropriate mechanisms. To operate the devices in a protected IT environment, Siemens recommends configuring the environment according to Siemensβ operational guidelines for industrial security and following recommendations in the product manuals.
Additional information on industrial security by Siemens can be found on the Siemens industrial security webpage.
For more information see Siemens Security Advisory SSA-145224
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. 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 cisa.gov/ics 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 cisa.gov/ics 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 high attack complexity.
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-37182
cert-portal.siemens.com/productcert/pdf/ssa-145224.pdf
cisa.gov/ics
cisa.gov/ics
cisasurvey.gov1.qualtrics.com/jfe/form/SV_9n4TtB8uttUPaM6?product=https://www.cisa.gov/news-events/ics-advisories/icsa-22-167-10
cwe.mitre.org/data/definitions/354.html
public.govdelivery.com/accounts/USDHSCISA/subscriber/new?topic_id=USDHSCISA_138
support.industry.siemens.com/cs/ww/en/ view/109809635/
twitter.com/CISAgov
twitter.com/intent/tweet?text=Siemens%20SCALANCE%20XM-400%20and%20XR-500+https://www.cisa.gov/news-events/ics-advisories/icsa-22-167-10
www.cisa.gov/uscert/ics/recommended-practices
www.cisa.gov/uscert/ics/tips/ICS-TIP-12-146-01B
www.cisa.gov/uscert/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-22-167-10&title=Siemens%20SCALANCE%20XM-400%20and%20XR-500
www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/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-22-167-10
www.oig.dhs.gov/
www.siemens.com/cert/operational-guidelines-industrial-security
www.siemens.com/industrialsecurity
www.usa.gov/
www.whitehouse.gov/
www.youtube.com/@cisagov
mailto:?subject=Siemens%20SCALANCE%20XM-400%20and%20XR-500&body=www.cisa.gov/news-events/ics-advisories/icsa-22-167-10
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
PARTIAL
AV:N/AC:M/Au:N/C:N/I:N/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS
Percentile
55.2%