Is CVE-2021-20610 actively exploited?

No active exploitation of CVE-2021-20610 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-20610 be exploited remotely?

Yes. CVE-2021-20610 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-20610?

CVE-2021-20610 has a CVSS score of 7.5 (HIGH).

HOME VULNERABILITIESCVE-2021-20610

HIGH

CVE-2021-20610

CWE-130Published: December 1, 2021· Updated: Jun 17, 2026

7.5

CVSS v3.1

Official Description

Improper Handling of Length Parameter Inconsistency 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.

NVD Source

Technical Analysis

CVE-2021-20610 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.

CVSS v3.1 Vector Breakdown

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges Req.None

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityNone

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Vendors & Products

mitsubishi110 product(s)

melsec iq-r r00 cpu firmwaremelsec iq-r r00 cpumelsec iq-r r01 cpu firmwaremelsec iq-r r01 cpumelsec iq-r r02 cpu firmwaremelsec iq-r r02 cpumelsec iq-r r04 cpu firmwaremelsec iq-r r04 cpumelsec iq-r r08 cpu firmwaremelsec iq-r r08 cpumelsec iq-r r120 cpu firmwaremelsec iq-r r120 cpu+98

Source: NVD CPE · 111 total CPE entries