No exploitation reportedFix available

CVE-2021-20589

No exploitation reported by the sources we read.

Published2021-05-19
WeaknessCWE-119

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

Buffer access with incorrect length value vulnerability in GOT2000 series GT27 model communication driver versions 01.19.000 through 01.38.000, GT25 model communication driver versions 01.19.000 through 01.38.000, GT23 model communication driver versions 01.19.000 through 01.38.000 and GT21 model communication driver versions 01.21.000 through 01.39.000, GOT SIMPLE series GS21 model communication driver versions 01.21.000 through 01.39.000, GT SoftGOT2000 versions 1.170C through 1.250L and Tension Controller LE7-40GU-L Screen package data for MODBUS/TCP V1.00 allows a remote unauthenticated attacker to stop the communication function of the products via specially crafted packets.

Timeline

dates in UTC

2021-05-1911:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 18:48 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-20589?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-20589?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Mitsubishi gs21 firmwareversion to verify

Branch	Affected	Fixed in	Source
1.x	≥ 01.21.000, ≤ 01.39.000	no fix published	NVD

Mitsubishi gt softgot2000 firmwareversion to verify

Branch	Affected	Fixed in	Source
1.x	≥ 1.170c, ≤ 1.250l	no fix published	NVD

Mitsubishi gt21 firmwareversion to verify

Branch	Affected	Fixed in	Source
1.x	≥ 01.21.000, ≤ 01.39.000	no fix published	NVD

3 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

ICSA-21-131-02 CISA7 known affected
Mitsubishi Electric GOT and Tension Controller (Update A)
GT23 model: Versions 01.19.000 - 01.38.000 · LE7-40GU-L Screen package data for MODBUS/TCP: v1.00 · GS21 model: Versions 01.21.000 - 01.39.000 · +4 more

Full record on NVD

Fix

Vendor fix CISA ICSA-21-131-02 · 7 productsGOT2000 series: GT21 model: update to 01.40.000 or later.
Mitigation from the vendor CISA ICSA-21-131-02 · 7 productsGOT2000 series: GT27 model, GT25 model, and GT23 model: update to 01.39.000 or later.
Mitigation from the vendor CISA ICSA-21-131-02 · 7 productsGOT SIMPLE series GS21 model: update to 01.40.000 or later.
Mitigation from the vendor CISA ICSA-21-131-02 · 7 productsGT SoftGOT2000: update to 1.255R or later.
Mitigation from the vendor CISA ICSA-21-131-02 · 7 productsLE7-40GU-L Screen package data for MODBUS/TCP: update to v1.01 or later.
Mitigation from the vendor CISA ICSA-21-131-02 · 7 productsPlease refer to the Mitsubishi Electric website for detailed update procedures.

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVSS 3.17.5read 2026-10-23
NVDCVSS 2.05read 2026-10-23
NVDweakness (CWE)CWE-119read 2026-10-23
FIRST EPSSEPSS score1.5 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: 2021-05-19
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-20589?

Is CVE-2021-20589 actively exploited?

Active exploitation of CVE-2021-20589 has not been confirmed. Its EPSS score was 1.5% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-20589?

CVE-2021-20589 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Hear about the next vulnerability in your software

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this product CISA KEV additions, October 2026 Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Following what attackers exploit right now? The CISA KEV additions of the month, with their patch deadlines.
Running this software? Vulnerability monitoring alerts you to new vulnerabilities in your products.

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database