CVE-2021-43556

HIGHNVD 7.87.8—

7.8

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.

CVSS v3: 7.8
EG Score: 7.8(medium)
EPSS: 70.1%
KEV: Not listed

Published

December 28, 2021

Last Modified

November 21, 2024

References (8)

ics-cert@hqhttps://us-cert.cisa.gov/ics/advisories/icsa-21-320-01
ics-cert@hqhttps://www.zerodayinitiative.com/advisories/ZDI-22-029/
ics-cert@hqhttps://www.zerodayinitiative.com/advisories/ZDI-22-031/
ics-cert@hqhttps://www.zerodayinitiative.com/advisories/ZDI-22-032/
af854a3a-2127-422b-91ae-364da2661108https://us-cert.cisa.gov/ics/advisories/icsa-21-320-01
af854a3a-2127-422b-91ae-364da2661108https://www.zerodayinitiative.com/advisories/ZDI-22-029/
af854a3a-2127-422b-91ae-364da2661108https://www.zerodayinitiative.com/advisories/ZDI-22-031/
af854a3a-2127-422b-91ae-364da2661108https://www.zerodayinitiative.com/advisories/ZDI-22-032/

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 9× in last 7d / 18× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-02 20:11 UTCepss_batch
2026-06-02 20:11 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 22:29 UTCepss_batch
2026-05-31 00:15 UTCepss_batch
2026-05-31 00:15 UTCepss_batch
2026-05-29 13:42 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-28 13:43 UTCepss_batch
2026-05-27 13:39 UTCepss_batch
2026-05-27 13:39 UTCepss_batch
2026-05-26 13:42 UTCepss_batch
2026-05-26 13:42 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 07:17 UTCepss_batch
2026-05-26 05:33 UTCEG score recompute
2026-05-26 05:33 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2021-43556?

CVE-2021-43556 is a high vulnerability published on December 28, 2021. 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.

When was CVE-2021-43556 disclosed?

CVE-2021-43556 was first published in the National Vulnerability Database on December 28, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-43556 actively exploited?

CVE-2021-43556 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 70.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-43556?

CVE-2021-43556 has a CVSS v3 base score of 7.8 (NVD).

How do I remediate CVE-2021-43556?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-43556, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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CVE-2021-43556

📅 Published

🔄 Last Modified

🔗 References (8)

Weakness Classification(2)

Data Freshness Timeline

❓ Frequently asked(5)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2021-43556?

🔗 Related CVEs(same CWE)

Same CWE

Published

Last Modified

References (8)

Frequently asked(5)

Related CVEs(same CWE)