No exploitation reported

CVE-2021-20590

No exploitation reported by the sources we read.

Published2021-04-22
WeaknessCWE-287

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

Improper authentication vulnerability in GOT2000 series GT27 model VNC server versions 01.39.010 and prior, GOT2000 series GT25 model VNC server versions 01.39.010 and prior, GOT2000 series GT21 model GT2107-WTBD VNC server versions 01.40.000 and prior, GOT2000 series GT21 model GT2107-WTSD VNC server versions 01.40.000 and prior, GOT SIMPLE series GS21 model GS2110-WTBD-N VNC server versions 01.40.000 and prior and GOT SIMPLE series GS21 model GS2107-WTBD-N VNC server versions 01.40.000 and prior allows a remote unauthenticated attacker to gain unauthorized access via specially crafted packets when the "VNC server" function is used.

Timeline

dates in UTC

2021-04-2219:15CVE 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-2021-20590?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-20590?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Mitsubishielectric got2000 gt25 firmwareversion to verify

Branch	Affected	Fixed in	Source
1.39	≤ 01.39.010	no fix published	NVD

Mitsubishielectric got2000 gt27 firmwareversion to verify

Branch	Affected	Fixed in	Source
1.39	≤ 01.39.010	no fix published	NVD

Mitsubishielectric gs2107-wtbd-n firmwareversion to verify

Branch	Affected	Fixed in	Source
1.40	≤ 01.40.000	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-21-112-02 CISA6 known affected
Mitsubishi Electric GOT (Update A)
GT2107-WTSD VNC server: Versions 01.40.000 and prior · GT25 model VNC server: Versions 01.39.010 and prior · GS2107-WTBD-N VNC server: Versions 01.40.000 and prior · +3 more

Full record on NVD

Fix

Mitigation from the vendor CISA ICSA-21-112-02 · 6 productsMitsubishi Electric instructs users to restrict access to the product only from trusted networks and hosts until they can update
Mitigation from the vendor CISA ICSA-21-112-02 · 6 productsGT27 model: VNC server Version 01.40.000 or later
Mitigation from the vendor CISA ICSA-21-112-02 · 6 productsGT25 model: VNC server Version 01.40.000 or later
Mitigation from the vendor CISA ICSA-21-112-02 · 6 productsGT2107-WTBD: VNC server Version 01.41.000 or later
Mitigation from the vendor CISA ICSA-21-112-02 · 6 productsGT2107-WTSD: VNC server Version 01.41.000 or later
Mitigation from the vendor CISA ICSA-21-112-02 · 6 productsGS2110-WTBD-N: VNC server Version 01.41.000 or later

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 2.04.3read 2026-10-23
NVDweakness (CWE)CWE-287read 2026-10-23
FIRST EPSSEPSS score1.3 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Published: 2021-04-22
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-20590?

Is CVE-2021-20590 actively exploited?

Active exploitation of CVE-2021-20590 has not been confirmed. Its EPSS score was 1.3% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-20590?

CVE-2021-20590 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:H/A:N.

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