CVE-2020-5543
TCP function included in the firmware of Mitsubishi Electric MELQIC IU1 series IU1-1M20-D firmware version 1.0.7 and earlier does not…
- Published
- Updated
- Reserved
- Assigned by
- jpcert
Description
TCP function included in the firmware of Mitsubishi Electric MELQIC IU1 series IU1-1M20-D firmware version 1.0.7 and earlier does not properly manage sessions, which allows remote attackers to stop the network functions or execute malware via a specially crafted packet.
Timeline
ID reserved
By jpcert
- 2 months later
· 2 months later
Published
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 2.2% · top 17% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Weakness
- Fails to manage sessions
- CWE-384 (opens in a new tab)All about CWE-384 and its CVEs
Affected products
Mitsubishi Electric Corporation · Mitsubishi Electric MELQIC IU1 series
- affected IU1-1M20-D firmware version 1.0.7 and earlier
References (2)
- https://jvn.jp/en/vu/JVNVU92370624/index.html (opens in a new tab)x_refsource_MISCx_transferred
- https://www.mitsubishielectric.co.jp/psirt/vulnerability/pdf/2019-004.pdf (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2020-5543)Record last updated .