How severe is CVE-2021-43882?

CVE-2021-43882 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-43882 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43882?

CVE-2021-43882 affects Microsoft Defender For Iot. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43882?

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-2021-43882 published?

CVE-2021-43882 was published on 2021-12-15 and last updated on 2026-06-17.

CVE-2021-43882

CVE-2021-43882 is a critical-severity vulnerability in Microsoft Defender For Iot with a CVSS 3.x base score of 9.0. 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-295.

Key facts

Severity: Critical (CVSS 3.x base score 9.0)
CVSS v2: 7.5
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Microsoft Defender For Iot
Published: 2021-12-15
Last modified: 2026-06-17

Description

Microsoft Defender for IoT Remote Code Execution Vulnerability

Frequently asked questions

What is CVE-2021-43882?: Microsoft Defender for IoT Remote Code Execution Vulnerability
How severe is CVE-2021-43882?: CVE-2021-43882 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over an adjacent network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-43882 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43882?: CVE-2021-43882 affects Microsoft Defender For Iot. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43882?: 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-2021-43882 published?: CVE-2021-43882 was published on 2021-12-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:microsoft:defender_for_iot:*:*:*:*:*:*:*:*

More vulnerabilities in Microsoft Defender For Iot

CVE-2021-42313 — Critical (CVSS 10.0): Microsoft Defender for IoT Remote Code Execution Vulnerability
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CVE-2024-29053 — High (CVSS 8.8): Microsoft Defender for IoT Remote Code Execution Vulnerability
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