How severe is CVE-2021-43936?

CVE-2021-43936 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-43936 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 36% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43936?

CVE-2021-43936 affects Webhmi Webhmi Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43936?

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

When was CVE-2021-43936 published?

CVE-2021-43936 was published on 2021-12-06 and last updated on 2026-06-17.

CVE-2021-43936

CVE-2021-43936 is a critical-severity vulnerability in Webhmi Webhmi Firmware with a CVSS 3.x base score of 10.0. Its EPSS exploit-prediction score of 36% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-434.

Key facts

Severity: Critical (CVSS 3.x base score 10.0)
CVSS v2: 10.0
EPSS exploit prediction: 36% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Webhmi Webhmi Firmware
Published: 2021-12-06
Last modified: 2026-06-17

Description

The software allows the attacker to upload or transfer files of dangerous types to the WebHMI portal, that may be automatically processed within the product's environment or lead to arbitrary code execution.

Frequently asked questions

What is CVE-2021-43936?: The software allows the attacker to upload or transfer files of dangerous types to the WebHMI portal, that may be automatically processed within the product's environment or lead to arbitrary code execution.
How severe is CVE-2021-43936?: CVE-2021-43936 has a CVSS 3.x base score of 10.0, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-43936 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 36% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43936?: CVE-2021-43936 affects Webhmi Webhmi Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43936?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-43936 published?: CVE-2021-43936 was published on 2021-12-06 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:webhmi:webhmi_firmware:*:*:*:*:*:*:*:*

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