6.5 Medium
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
SINGLE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:L/Au:S/C:P/I:P/A:P
7.2 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
7.3 High
AI Score
Confidence
High
0.001 Low
EPSS
Percentile
39.5%
This updated advisory is a follow-up to the advisory update titled ICSA-19-192-02 Siemens SIMATIC WinCC and PCS7 (Update B) that was published September 10, 2019, on the ICS webpage of us-cert.gov.
Successful exploitation of this vulnerability could cause a denial-of-service condition on the affected service or device.
The following Siemens industrial products are affected:
--------- Begin Update C Part 1 of 2 --------
--------- End Update C Part 1 of 2 --------
The SIMATIC WinCC DataMonitor web application of the affected products allows an authenticated user with network access to the WinCC DataMonitor application to upload arbitrary ASPX code.
Successful exploitation requires no user interaction and may impact the confidentiality, integrity, and availability of the affected device. The vulnerability is relevant only in situations where an attacker has access via the web interface but not to the directory structure.
CVE-2019-10935 has been assigned to this vulnerability. A CVSS v3 base score of 7.2 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H).
Xuchen Zhu from ZheJiang Guoli Security Technology and CNCERT/CC reported this vulnerability to Siemens.
Siemens currently has updates for the following products:
--------- Begin Update C Part 2 of 2 --------
--------- End Update C Part 2 of 2 ---------
For the balance of the listed products, Siemens is preparing further updates and recommends users apply the following specific workarounds and mitigations to reduce risk until patches are available:
Siemens recommends users configure their environment according to Siemensβ operational guidelines for industrial security (Download) 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 on the vulnerability and more detailed mitigation instructions, please see Siemens security advisory SSA-121293 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 this vulnerability.
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2019-10935
www.siemens.com/cert/advisories
assets.new.siemens.com/siemens/assets/public.1502968141.411e91564a2d259ecd4b6c79b51f89c044b3de81.operational-guidelines-industrial-security-en.pdf
cwe.mitre.org/data/definitions/434.html
ics-cert.us-cert.gov/alerts/ICS-ALERT-10-301-01
public.govdelivery.com/accounts/USDHSCISA/subscriber/new?topic_id=USDHSCISA_138
support.industry.siemens.com/cs/ww/en/view/109747387
support.industry.siemens.com/cs/ww/en/view/109747394
support.industry.siemens.com/cs/ww/en/view/109763890
support.industry.siemens.com/cs/ww/en/view/109763892
support.industry.siemens.com/cs/ww/en/view/109767227
support.industry.siemens.com/cs/ww/en/view/109768093
support.industry.siemens.com/cs/ww/en/view/109768093
support.industry.siemens.com/cs/ww/en/view/109768093
support.industry.siemens.com/cs/ww/en/view/109768972
support.industry.siemens.com/cs/ww/en/view/109768972
twitter.com/CISAgov
twitter.com/intent/tweet?text=Siemens%20SIMATIC%20WinCC%20and%20PCS7%20%28Update%20C%29+https://www.cisa.gov/news-events/ics-advisories/icsa-19-192-02
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-19-192-02&title=Siemens%20SIMATIC%20WinCC%20and%20PCS7%20%28Update%20C%29
www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:H/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-19-192-02
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-19-192-02
www.us-cert.gov/ics
www.us-cert.gov/ics
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%20WinCC%20and%20PCS7%20%28Update%20C%29&body=www.cisa.gov/news-events/ics-advisories/icsa-19-192-02
6.5 Medium
CVSS2
Attack Vector
NETWORK
Attack Complexity
LOW
Authentication
SINGLE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:L/Au:S/C:P/I:P/A:P
7.2 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
HIGH
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
7.3 High
AI Score
Confidence
High
0.001 Low
EPSS
Percentile
39.5%