{"cve":"CVE-2021-20610","nvd":{"published":"2021-12-01T16:15:07.510","modified":"2026-06-17T03:34:06.860","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-130"],"references":["https://jvn.jp/vu/JVNVU94434051/index.html","https://us-cert.cisa.gov/ics/advisories/icsa-21-334-02","https://www.mitsubishielectric.com/en/psirt/vulnerability/pdf/2021-019_en.pdf","https://jvn.jp/vu/JVNVU94434051/index.html","https://us-cert.cisa.gov/ics/advisories/icsa-21-334-02"],"products":["mitsubishi:melipc_mi5122-vw_firmware","mitsubishi:melsec_iq-r_r00_cpu_firmware","mitsubishi:melsec_iq-r_r01_cpu_firmware","mitsubishi:melsec_iq-r_r02_cpu_firmware","mitsubishi:melsec_iq-r_r04_cpu_firmware","mitsubishi:melsec_iq-r_r04_pcpu_firmware","mitsubishi:melsec_iq-r_r08_cpu_firmware","mitsubishi:melsec_iq-r_r08_pcpu_firmware","mitsubishi:melsec_iq-r_r08_sfcpu_firmware","mitsubishi:melsec_iq-r_r120_cpu_firmware","mitsubishi:melsec_iq-r_r120_pcpu_firmware","mitsubishi:melsec_iq-r_r120_sfcpu_firmware","mitsubishi:melsec_iq-r_r12_ccpu-v_firmware","mitsubishi:melsec_iq-r_r16_cpu_firmware","mitsubishi:melsec_iq-r_r16_mtcpu_firmware","mitsubishi:melsec_iq-r_r16_pcpu_firmware","mitsubishi:melsec_iq-r_r16_sfcpu_firmware","mitsubishi:melsec_iq-r_r32_cpu_firmware","mitsubishi:melsec_iq-r_r32_mtcpu_firmware","mitsubishi:melsec_iq-r_r32_pcpu_firmware","mitsubishi:melsec_iq-r_r32_sfcpu_firmware","mitsubishi:melsec_iq-r_r64_mtcpu_firmware","mitsubishi:melsec_l02cpu\\(-p\\)_firmware","mitsubishi:melsec_l06cpu\\(-p\\)_firmware","mitsubishi:melsec_l26cpu-\\(p\\)bt_firmware","mitsubishi:melsec_l26cpu\\(-p\\)_firmware","mitsubishi:melsec_mr-mq100_firmware","mitsubishi:melsec_q03udecpu_firmware","mitsubishi:melsec_q03udvcpu_firmware","mitsubishi:melsec_q04udecpu_firmware","mitsubishi:melsec_q04udpvcpu_firmware","mitsubishi:melsec_q04udvcpu_firmware","mitsubishi:melsec_q06udecpu_firmware","mitsubishi:melsec_q06udpvcpu_firmware","mitsubishi:melsec_q06udvcpu_firmware","mitsubishi:melsec_q100udecpu_firmware","mitsubishi:melsec_q10udecpu_firmware","mitsubishi:melsec_q12dccpu-v_firmware","mitsubishi:melsec_q13udecpu_firmware","mitsubishi:melsec_q13udpvcpu_firmware","mitsubishi:melsec_q13udvcpu_firmware","mitsubishi:melsec_q170mcpu_firmware","mitsubishi:melsec_q170mscpu\\(-s1\\)_firmware","mitsubishi:melsec_q172dcpu-s1_firmware","mitsubishi:melsec_q172dscpu_firmware","mitsubishi:melsec_q173dcpu-s1_firmware","mitsubishi:melsec_q173dscpu_firmware","mitsubishi:melsec_q20udecpu_firmware","mitsubishi:melsec_q24dhccpu-ls_firmware","mitsubishi:melsec_q24dhccpu-v\\(g\\)_firmware"],"source":"nvd","synced_at":"2026-10-19T21:25:41.256909649+00:00"},"epss":{"cve":"CVE-2021-20610","score":0.03273,"percentile":0.88415,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}