High severity7.5NVD Advisory· Published Dec 1, 2021· Updated Jun 17, 2026

CVE-2021-20611

Description

Improper Input Validation 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.

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Affected products

127

Mitsubishielectric/MELSEC iQ-R Seriescpe-rescue29 versions
Firmware versions "24" and prior+ 28 more
- (no CPE)range: Firmware versions "24" and prior
- (no CPE)range: Firmware versions "24" and prior
- (no CPE)range: Firmware versions "24" and prior
- (no CPE)range: Firmware versions "57" and prior
- (no CPE)range: Firmware versions "57" and prior
- (no CPE)range: Firmware versions "57" and prior
- (no CPE)range: Firmware versions "57" and prior
- (no CPE)range: Firmware versions "57" and prior
- (no CPE)range: Firmware versions "57" and prior
- (no CPE)range: Firmware versions "57" and prior
- (no CPE)range: Firmware versions "57" and prior
- (no CPE)range: Firmware versions "57" and prior
- (no CPE)range: Firmware versions "57" and prior
- (no CPE)range: Firmware versions "26" and prior
- (no CPE)range: Firmware versions "26" and prior
- (no CPE)range: Firmware versions "26" and prior
- (no CPE)range: Firmware versions "26" and prior
- (no CPE)range: Firmware versions "29" and prior
- (no CPE)range: Firmware versions "29" and prior
- (no CPE)range: Firmware versions "29" and prior
- (no CPE)range: Firmware versions "29" and prior
- (no CPE)range: Firmware versions "08" and prior
- (no CPE)range: Firmware versions "08" and prior
- (no CPE)range: Firmware versions "08" and prior
- (no CPE)range: Firmware versions "08" and prior
- (no CPE)range: Operating system software version "23" and prior
- (no CPE)range: Operating system software version "23" and prior
- (no CPE)range: Operating system software version "23" and prior
- (no CPE)range: Firmware versions "16" and prior
Mitsubishielectric/MELSEC-Q Series Q03UDVCPUcpe-rescue18 versions
The first 5 digits of serial No. "23121" and prior+ 17 more
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23071" and prior
- (no CPE)range: The first 5 digits of serial No. "23071" and prior
- (no CPE)range: The first 5 digits of serial No. "23071" and prior
- (no CPE)range: The first 5 digits of serial No. "23071" and prior
- (no CPE)range: The first 5 digits of serial No. "23071" and prior
- (no CPE)range: The first 5 digits of serial No. "23071" and prior
- (no CPE)range: The first 5 digits of serial No. "23071" and prior
- (no CPE)range: The first 5 digits of serial No. "23071" and prior
- (no CPE)range: The first 5 digits of serial No. "23071" and prior
- (no CPE)range: Operating system software version "Y" and prior
- (no CPE)range: Operating system software version "Y" and prior
- (no CPE)range: Operating system software version "W" and prior
- (no CPE)range: Operating system software version "Y" and prior
- (no CPE)
Mitsubishielectric/MELSEC-Q Seriescpe-rescue17 versions
The first 5 digits of serial No. "23121" and prior+ 16 more
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: Operating system software version "W" and prior
- (no CPE)range: Operating system software version "W" and prior
- (no CPE)range: Operating system software version "Y" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "24031" and prior
- (no CPE)range: The first 5 digits of serial No. "24031" and prior
- (no CPE)range: The first 5 digits of serial No. "24031" and prior
- (no CPE)range: The first 5 digits of serial No. "24031" and prior
- (no CPE)range: The first 5 digits of serial No. "24031" and prior
- (no CPE)range: Operating system software version "F" and prior
Mitsubishielectric/Melsec Iq R R00 Cpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r00_cpu_firmware:*:*:*:*:*:*:*:*
Range: <=24
Mitsubishielectric/Melsec Iq R R01 Cpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r01_cpu_firmware:*:*:*:*:*:*:*:*
Range: <=24
Mitsubishielectric/Melsec Iq R R02 Cpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r02_cpu_firmware:*:*:*:*:*:*:*:*
Range: <=24
Mitsubishielectric/Melsec Iq R R04 Cpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r04_cpu_firmware:*:*:*:*:*:*:*:*
Range: <=57
Mitsubishielectric/Melsec Iq R R08 Cpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r08_cpu_firmware:*:*:*:*:*:*:*:*
Range: <=57
Mitsubishielectric/Melsec Iq R R120 Cpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r120_cpu_firmware:*:*:*:*:*:*:*:*
Range: <=57
Mitsubishielectric/Melsec Iq R R16 Cpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r16_cpu_firmware:*:*:*:*:*:*:*:*
Range: <=57
Mitsubishielectric/Melsec Iq R R32 Cpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r32_cpu_firmware:*:*:*:*:*:*:*:*
Range: <=57
Mitsubishielectric/Melsec Iq R R04 Pcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r04_pcpu_firmware:*:*:*:*:*:*:*:*
Range: <=29
Mitsubishielectric/Melsec Iq R R08 Pcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r08_pcpu_firmware:*:*:*:*:*:*:*:*
Range: <=29
Mitsubishielectric/Melsec Iq R R16 Pcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r16_pcpu_firmware:*:*:*:*:*:*:*:*
Range: <=29
Mitsubishielectric/Melsec Iq R R32 Pcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r32_pcpu_firmware:*:*:*:*:*:*:*:*
Range: <=29
Mitsubishielectric/Melsec Iq R R120 Pcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r120_pcpu_firmware:*:*:*:*:*:*:*:*
Range: <=29
Mitsubishielectric/Melsec Iq R R08 Sfcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r08_sfcpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Iq R R16 Sfcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r16_sfcpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Iq R R32 Sfcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r32_sfcpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Iq R R120 Sfcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r120_sfcpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Iq R R16 Mtcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r16_mtcpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Iq R R32 Mtcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r32_mtcpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Iq R R64 Mtcpu Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r64_mtcpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Iq R R12 Ccpu V Firmware
cpe:2.3:o:mitsubishi:melsec_iq-r_r12_ccpu-v_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q03udecpu Firmware
cpe:2.3:o:mitsubishi:melsec_q03udecpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q04udecpu Firmware
cpe:2.3:o:mitsubishi:melsec_q04udecpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q06udecpu Firmware
cpe:2.3:o:mitsubishi:melsec_q06udecpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q10udecpu Firmware
cpe:2.3:o:mitsubishi:melsec_q10udecpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q13udecpu Firmware
cpe:2.3:o:mitsubishi:melsec_q13udecpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q20udecpu Firmware
cpe:2.3:o:mitsubishi:melsec_q20udecpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q26udecpu Firmware
cpe:2.3:o:mitsubishi:melsec_q26udecpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q50udecpu Firmware
cpe:2.3:o:mitsubishi:melsec_q50udecpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q100udecpu Firmware
cpe:2.3:o:mitsubishi:melsec_q100udecpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q03udvcpu Firmware
cpe:2.3:o:mitsubishi:melsec_q03udvcpu_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q04udvcpu Firmware
cpe:2.3:o:mitsubishi:melsec_q04udvcpu_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q06udvcpu Firmware
cpe:2.3:o:mitsubishi:melsec_q06udvcpu_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q13udvcpu Firmware
cpe:2.3:o:mitsubishi:melsec_q13udvcpu_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q26udvcpu Firmware
cpe:2.3:o:mitsubishi:melsec_q26udvcpu_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q04udpvcpu Firmware
cpe:2.3:o:mitsubishi:melsec_q04udpvcpu_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q06udpvcpu Firmware
cpe:2.3:o:mitsubishi:melsec_q06udpvcpu_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q13udpvcpu Firmware
cpe:2.3:o:mitsubishi:melsec_q13udpvcpu_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q26udpvcpu Firmware
cpe:2.3:o:mitsubishi:melsec_q26udpvcpu_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q12dccpu V Firmware
cpe:2.3:o:mitsubishi:melsec_q12dccpu-v_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q24dhccpu V\(g\) Firmware
cpe:2.3:o:mitsubishi:melsec_q24dhccpu-v\(g\)_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q24dhccpu Ls Firmware
cpe:2.3:o:mitsubishi:melsec_q24dhccpu-ls_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q26dhccpu Ls Firmware
cpe:2.3:o:mitsubishi:melsec_q26dhccpu-ls_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Mr Mq100 Firmware
cpe:2.3:o:mitsubishi:melsec_mr-mq100_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q172dcpu S1 Firmware
cpe:2.3:o:mitsubishi:melsec_q172dcpu-s1_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q173dcpu S1 Firmware
cpe:2.3:o:mitsubishi:melsec_q173dcpu-s1_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q172dscpu Firmware
cpe:2.3:o:mitsubishi:melsec_q172dscpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q173dscpu Firmware
cpe:2.3:o:mitsubishi:melsec_q173dscpu_firmware:-:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q170mscpu\( S1\) Firmware
cpe:2.3:o:mitsubishi:melsec_q170mscpu\(-s1\)_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec Q170mcpu Firmware
cpe:2.3:o:mitsubishi:melsec_q170mcpu_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melipc Mi5122 Vw Firmware
cpe:2.3:o:mitsubishi:melipc_mi5122-vw_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec L26cpu \(p\)bt Firmware
cpe:2.3:o:mitsubishi:melsec_l26cpu-\(p\)bt_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec L26cpu\( P\) Firmware
cpe:2.3:o:mitsubishi:melsec_l26cpu\(-p\)_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec L06cpu\( P\) Firmware
cpe:2.3:o:mitsubishi:melsec_l06cpu\(-p\)_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/Melsec L02cpu\( P\) Firmware
cpe:2.3:o:mitsubishi:melsec_l02cpu\(-p\)_firmware:*:*:*:*:*:*:*:*
Mitsubishielectric/MELSEC L Series L02/06/26CPU(-P)cpe-rescue5 versions
The first 5 digits of serial No. "23121" and prior+ 4 more
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
- (no CPE)range: The first 5 digits of serial No. "23121" and prior
Mitsubishielectric/MELSEC L Series L02/06/26CPUcpe-rescue
Range: The first 5 digits of serial No. "23121" and prior
Mitsubishielectric/MELSEC iQ-R Series R00/01/02CPU Firmwarellm-fuzzy
Mitsubishielectric/MELIPC Series MI5122-VWcpe-rescue
Range: Firmware versions "05" and prior

Patches

Vulnerability mechanics

References

jvn.jp/vu/JVNVU94434051/index.htmlnvdThird Party Advisory
us-cert.cisa.gov/ics/advisories/icsa-21-334-02nvdThird Party AdvisoryUS Government Resource
www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2021-019_en.pdfnvdVendor Advisory

News mentions

No linked articles in our index yet.

cvss	0.488
epss	0.002
exploit	0.000
kev	0.000
patch	0.000
ransomware	0.000