10 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
9.6 High
AI Score
Confidence
High
0.005 Low
EPSS
Percentile
76.6%
Successful exploitation of these vulnerabilities could lead to remote code execution and denial-of-service conditions.
The following versions of Experion PKS, a process control system, are affected:
The affected product is vulnerable to unrestricted file uploads, which may allow an attacker to remotely execute arbitrary code and cause a denial-of-service condition.
CVE-2021-38397 has been assigned to this vulnerability. A CVSS v3 base score of 10.0 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H).
The affected product is vulnerable to improper neutralization of special elements in output, which may allow an attacker to remotely execute arbitrary code and cause a denial-of-service condition.
CVE-2021-38395 has been assigned to this vulnerability. A CVSS v3 base score of 9.1 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H).
The affected product is vulnerable to relative path traversal, which may allow an attacker access to unauthorized files and directories.
CVE-2021-38399 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been assigned; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).
Rei Henigman and Nadav Erez of Claroty reported these vulnerabilities to CISA.
Honeywell recommends users follow all guidance in the Experion Network and Security Planning Guide to prevent attacks by malicious actors.
Additional information can be found in Honeywell Support document SN2021-02-22-01.
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-12-146-01B–Targeted 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-2021-38395
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-38397
web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-38399
cwe.mitre.org/data/definitions/23.html
cwe.mitre.org/data/definitions/434.html
cwe.mitre.org/data/definitions/74.html
public.govdelivery.com/accounts/USDHSCISA/subscriber/new?topic_id=USDHSCISA_138
twitter.com/CISAgov
twitter.com/intent/tweet?text=Honeywell%20Experion%20PKS%20and%20ACE%20Controllers+https://www.cisa.gov/news-events/ics-advisories/icsa-21-278-04
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
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www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
www.honeywellprocess.com/library/support/Documents/Experion/Network-and-Security-Planning-Guide-EPDOC-XX75-en-511C.pdf
www.honeywellprocess.com/library/support/notifications/Customer/SN2021-02-22-01-Experion-C300-CCL.pdf
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www.usa.gov/
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mailto:?subject=Honeywell%20Experion%20PKS%20and%20ACE%20Controllers&body=www.cisa.gov/news-events/ics-advisories/icsa-21-278-04
10 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
9.6 High
AI Score
Confidence
High
0.005 Low
EPSS
Percentile
76.6%