9.1 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
9.3 High
AI Score
Confidence
High
0.003 Low
EPSS
Percentile
70.1%
This updated advisory is a follow-up to the original advisory titled ICSA-23-017-02 Mitsubishi Electric MELSEC iQ-F, iQ-R Series (Update A) that was published January 17, 2023, on the ICS webpage on cisa.gov/ICS.
Successful exploitation of this vulnerability could allow an attacker to access the WEB server function by guessing the random numbers used for authentication.
The following Mitsubishi Electric MELSEC products are affected:
--------- Begin Update B Part 1 of 3 ---------
--------- End Update B Part 1 of 3 ---------
4.2.1 PREDICTABLE SEED IN PSEUDO-RANDOM NUMBER GENERATOR (PRNG) CWE-337
Mitsubishi Electric MELSEC iQ-F and iQ-R Series products both contain an authentication bypass vulnerability in the WEB server function due to predictable seed in the pseudo-random number generator.
CVE-2022-40267 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:H/A:N).
Matt Wiseman of Cisco Talos reported this vulnerability to Mitsubishi Electric.
Mitsubishi Electric has fixed the following products and recommends users apply the latest firmware update to the follow products:
--------- Begin Update B part 2 of 3 ---------
--------- End Update B part 2 of 3 ---------
Refer to the following product manual for updating the firmware:
β5 FIRMWARE UPDATE FUNCTIONβ in the MELSEC iQ-F FX5 Userβs Manual (Application)
--------- Begin Update B part 3 of 3 ---------
MELSEC iQ-R Module Configuration Manual βAppendix 2 Firmware Update Functionβ
--------- End Update B part 3 of 3 ---------
Mitsubishi Electric recommends users take the following mitigation measures to minimize the risk of exploiting this vulnerability:
CISA also provides a section for control systems security recommended practices on the ICS webpage at cisa.gov/ics. Several CISA products detailing cyber defense best 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 at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01BβTargeted Cyber Intrusion Detection and Mitigation Strategies.
Organizations observing suspected malicious activity should follow established internal procedures and report 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-2022-40267
cisa.gov/ics
cisa.gov/ics
cwe.mitre.org/data/definitions/337.html
public.govdelivery.com/accounts/USDHSCISA/subscriber/new?topic_id=USDHSCISA_138
twitter.com/CISAgov
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us-cert.cisa.gov/ics/Recommended-Practices
us-cert.cisa.gov/sites/default/files/recommended_practices/NCCIC_ICS-CERT_Defense_in_Depth_2016_S508C.pdf
www.cisa.gov/uscert/ics/tips/ICS-TIP-12-146-01B
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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:N/S:U/C:N/I:H/A:N
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www.mitsubishielectric.com/fa/download/index.html
www.oig.dhs.gov/
www.surveymonkey.com/r/CISA-cyber-survey?product=https://www.cisa.gov/news-events/ics-advisories/icsa-23-017-02
www.usa.gov/
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mailto:?subject=Mitsubishi%20Electric%20MELSEC%20iQ-F%2C%20iQ-R%20Series%20%28Update%20B%29&body=www.cisa.gov/news-events/ics-advisories/icsa-23-017-02
9.1 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
9.3 High
AI Score
Confidence
High
0.003 Low
EPSS
Percentile
70.1%