How severe is CVE-2021-43556?

CVE-2021-43556 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-43556 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43556?

CVE-2021-43556 affects Fatek Winproladder. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43556?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-43556 published?

CVE-2021-43556 was published on 2021-12-28 and last updated on 2026-06-17.

CVE-2021-43556

CVE-2021-43556 is a high-severity vulnerability in Fatek Winproladder with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 6.8
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Fatek Winproladder
Published: 2021-12-28
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2021-43556?: 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.
How severe is CVE-2021-43556?: CVE-2021-43556 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-43556 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43556?: CVE-2021-43556 affects Fatek Winproladder. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43556?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-43556 published?: CVE-2021-43556 was published on 2021-12-28 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:fatek:winproladder:*:*:*:*:*:*:*:*

More vulnerabilities in Fatek Winproladder

CVE-2021-32992 — Critical (CVSS 9.8): FATEK Automation WinProladder Versions 3.30 and prior do not properly restrict operations within the bounds of a memory…
CVE-2021-32990 — Critical (CVSS 9.8): FATEK Automation WinProladder Versions 3.30 and prior are vulnerable to an out-of-bounds read, which may allow an…
CVE-2021-32988 — Critical (CVSS 9.8): FATEK Automation WinProladder Versions 3.30 and prior are vulnerable to an out-of-bounds write, which may allow an…
CVE-2021-43554 — High (CVSS 7.8): FATEK WinProladder Versions 3.30_24518 and prior are vulnerable to an out-of-bounds write while processing project…
CVE-2021-38442 — High (CVSS 7.8): FATEK Automation WinProladder versions 3.30 and prior lacks proper validation of user-supplied data when parsing…
CVE-2021-38438 — High (CVSS 7.8): A use after free vulnerability in FATEK Automation WinProladder versions 3.30 and prior may be exploited when a valid…

All CVEs affecting Fatek Winproladder →

Other CWE-787 (Out-of-bounds Write) vulnerabilities

CVE-2026-42369 — Critical (CVSS 10.0): GV-VMS V20 is a Video Monitoring Software used to gather the feeds of many surveillance cameras and manage other…
CVE-2026-4746 — Critical (CVSS 10.0): Out-of-bounds Write vulnerability in timeplus-io proton (base/poco/Foundation/src‎ modules). This vulnerability is…
CVE-2025-43300 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS…
CVE-2025-24201 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in…
CVE-2024-42479 — Critical (CVSS 10.0): llama.cpp provides LLM inference in C/C++. The unsafe `data` pointer member in the `rpc_tensor` structure can cause…
CVE-2024-39791 — Critical (CVSS 10.0): Stack-based buffer overflow vulnerabilities affecting Vonets industrial wifi bridge relays and wifi bridge…

Browse all CWE-787 (Out-of-bounds Write) vulnerabilities →