CVE-2021-43556

mediumpriority · track · 32EPSS 0.022 · 83 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

2.22% (83rd) EPSS

CVSS 6.8 · medium

Is it mine?

5 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisa_csaf_ot

EPSS · scored 2026-10-27

FATEK WinProladder Versions 3.30_24518 and prior are vulnerable to a stack-based buffer overflow while processing project files, which may allow an attacker to execute arbitrary code.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

No vendor fix yet; a mitigation is available.

MitigationWinProladdercisa_csaf_ot
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cvss

Technical severity, 0–10. One row per scoring source.

7.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.8–7.8

v2.06.8mediumAV:N/AC:M/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 6.4

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 5.9

v3.07.8highCVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · CISA US

v3.17.8highAV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · ENISA EU

v3.17.8highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:Hsecondary · ics-cert@hq.dhs.gov USexploitability 1.8 · impact 5.9

v3.17.1highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-787USprimaryCWE-121USCWE-121USCWE-121US

affected products (5)

Products and version ranges known to be affected.

WinProladder: Versions 3.30_24518 and priorall versionscisa_csaf_otUS
FATEK Automation WinProladder≤ 3.30_24518cisa_csaf_otUS
FATEK Automation WinProladder≤ All ≤3.30_24518enisa_euvdEU
FATEK Automation WinProladder≤ 3.30_24518fstec_bduRU
fatek winproladder≤ 3.30_24518nvdUScpe:2.3:a:fatek:winproladder:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

ICSA-21-320-01FATEK Automation WinProladder2021-11-16icsa · cisa_csaf_otUS
Successful exploitation of these vulnerabilities could allow for arbitrary code execution.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisa_csaf_ot nvd NVD CVE.org MITRE

published 2021-12-28modified 2026-06-17

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+16132 more

references (13)

External citations — patches, advisories, analysis.

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