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
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
AI Score
Confidence
High
EPSS
Percentile
55.3%
Successful exploitation of this vulnerability may prevent the FTP client from connecting to the FTP server on MELSEC-Q Series and MELSEC-L Series CPU module.
Only FTP server function is affected by this vulnerability.
The following versions of MELSEC-Q Series and MELSEC-L Series CPU modules are affected:
A remote attacker can cause the FTP service to enter a denial-of-service condition dependent on the timing at which a remote attacker connects to the FTP server on the above CPU modules.
CVE-2019-13555 has been assigned to this vulnerability. A CVSS v3 base score of 7.5 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).
Tri Quach of Amazonβs Customer Fulfillment Technology Security (CFTS) group reported this vulnerability to CISA.
Mitsubishi Electric has produced a new version of the firmware. Additional information about this vulnerability or Mitsubishi Electricβs compensating control is available by contacting a local Mitsubishi Electric representative, which can be found at the following location:
<https://us.mitsubishielectric.com/fa/en/about-us/distributors>
Mitsubishi Electric strongly recommends that users should operate the affected device behind a firewall.
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-2019-13555
cisasurvey.gov1.qualtrics.com/jfe/form/SV_9n4TtB8uttUPaM6?product=https://www.cisa.gov/news-events/ics-advisories/icsa-19-311-01
cwe.mitre.org/data/definitions/400.html
public.govdelivery.com/accounts/USDHSCISA/subscriber/new?topic_id=USDHSCISA_138
twitter.com/CISAgov
twitter.com/intent/tweet?text=Mitsubishi%20Electric%20MELSEC-Q%20Series%20and%20MELSEC-L%20Series%20CPU%20Modules+https://www.cisa.gov/news-events/ics-advisories/icsa-19-311-01
us.mitsubishielectric.com/fa/en/about-us/distributors
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-19-311-01&title=Mitsubishi%20Electric%20MELSEC-Q%20Series%20and%20MELSEC-L%20Series%20CPU%20Modules
www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/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-19-311-01
www.oig.dhs.gov/
www.us-cert.gov/ics
www.us-cert.gov/ics
www.us-cert.gov/ics/alerts/ICS-ALERT-10-301-01
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=Mitsubishi%20Electric%20MELSEC-Q%20Series%20and%20MELSEC-L%20Series%20CPU%20Modules&body=www.cisa.gov/news-events/ics-advisories/icsa-19-311-01
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
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
NONE
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
AI Score
Confidence
High
EPSS
Percentile
55.3%