No exploitation reportedFix available

CVE-2021-43555

No exploitation reported by the sources we read.

Published2021-11-19
WeaknessCWE-22 · CWE-23

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

mySCADA myDESIGNER Versions 8.20.0 and prior fails to properly validate contents of an imported project file, which may make the product vulnerable to a path traversal payload. This vulnerability may allow an attacker to plant files on the file system in arbitrary locations or overwrite existing files, resulting in remote code execution.

Timeline

dates in UTC

2021-11-1919:15CVE publishedNVD
2026-10-2319:23EPSS crossed 10 %FIRST EPSS

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 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-2021-43555?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-43555?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Myscada mydesigner

Branch	Affected	Fixed in	Source
8.20	≤ 8.20.0	no fix published	NVD

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-21-313-04 CISA1 known affected
mySCADA myDESIGNER
myDESIGNER: Versions 8.20.0 and prior

Full record on NVD

Fix

Mitigation from the vendor CISA ICSA-21-313-04 · 1 productmySCADA recommends users apply update v8.22.0 or later.
Mitigation from the vendor CISA ICSA-21-313-04 · 1 productUpgrade note: RFID card access has been redesigned. If a user uses an RFID card to login, the user will need to re-enter the password for all RFID users in the project after the update is applied.

Advisories and patches

us-cert.cisa.govPatch

Detection

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

Sources

CNACVSS 3.17.3read 2026-10-23
NVDCVSS 3.17.8read 2026-10-23
NVDCVSS 2.06.8read 2026-10-23
CNAweakness (CWE)CWE-23read 2026-10-23
NVDweakness (CWE)CWE-22read 2026-10-23
FIRST EPSSEPSS score38.2 %read 2026-10-23

Technical details

CVSS v3 Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Published: 2021-11-19
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-43555?

Is CVE-2021-43555 actively exploited?

Active exploitation of CVE-2021-43555 has not been confirmed. Its EPSS score was 38.2% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-43555?

CVE-2021-43555 has a CVSS v3 base score of 7.8 (HIGH severity), with vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

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