THREATPORT/VULNERABILITY/CVE-2021-20609
HIGH SEVERITY

CVE-2021-20609

Melsec Iq R R00 Cpu Firmware vulnerability

CVSS
7.5
EPSS
3.1%
EPSS pct
86th
Exploited
No known
Uncontrolled Resource Consumption vulnerability in Mitsubishi Electric MELSEC iQ-R Series R00/01/02CPU, MELSEC iQ-R Series R04/08/16/32/120(EN)CPU, MELSEC iQ-R Series R08/16/32/120SFCPU, MELSEC iQ-R Series R08/16/32/120PCPU, MELSEC iQ-R Series R08/16/32/120PSFCPU, MELSEC iQ-R Series R16/32/64MTCPU, MELSEC iQ-R Series R12CCPU-V, MELSEC Q Series Q03UDECPU, MELSEC Q Series Q04/06/10/13/20/26/50/100UDEHCPU, MELSEC Q Series Q03/04/06/13/26UDVCPU, MELSEC Q Series Q04/06/13/26UDPVCPU, MELSEC Q Series Q12DCCPU-V, MELSEC Q Series Q24DHCCPU-V(G), MELSEC Q Series Q24/26DHCCPU-LS, MELSEC Q Series MR-MQ100, MELSEC Q Series Q172/173DCPU-S1, MELSEC Q Series Q172/173DSCPU, MELSEC Q Series Q170MCPU, MELSEC Q Series Q170MSCPU(-S1), MELSEC L Series L02/06/26CPU(-P), MELSEC L Series L26CPU-(P)BT and MELIPC Series MI5122-VW allows a remote unauthenticated attacker to cause a denial-of-service (DoS) condition by sending specially crafted packets. System reset is required for recovery.
Affected vendor
Mitsubishi
Affected product
Melsec Iq R R00 Cpu Firmware
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness type (CWE)
  • CWE-400 — Uncontrolled Resource Consumption
Published
2021-12-01

Risk analysis

Based on its CVSS vector, this vulnerability is exploitable over the network, low attack complexity, requiring no privileges, no user interaction. Successful exploitation leads to high impact to availability.

Its EPSS score of 3.1% reflects a lower probability of exploitation activity in the wild over the next 30 days, placing it above 86% of all scored CVEs.

Check your external exposure to CVE-2021-20609

  • Confirm whether Mitsubishi Melsec Iq R R00 Cpu Firmware is running on any internet-facing host or subdomain.
  • Match discovered service fingerprints against the version affected by CVE-2021-20609.
  • Prioritise remediation if the asset is public, business-critical, or near authentication/payment flows.

How ThreatPort helps with CVE-2021-20609

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