How severe is CVE-2020-16875?

CVE-2020-16875 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-16875 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 47% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-16875?

CVE-2020-16875 primarily affects Microsoft Exchange Server. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-16875?

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-2020-16875 published?

CVE-2020-16875 was published on 2020-09-11 and last updated on 2026-06-17.

CVE-2020-16875

CVE-2020-16875 is a high-severity vulnerability in Microsoft Exchange Server with a CVSS 3.x base score of 8.4. Its EPSS exploit-prediction score of 47% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-74.

Key facts

Severity: High (CVSS 3.x base score 8.4)
CVSS v2: 9.0
EPSS exploit prediction: 47% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-74
Affected product: Microsoft Exchange Server
Published: 2020-09-11
Last modified: 2026-06-17

Description

A remote code execution vulnerability exists in Microsoft Exchange server due to improper validation of cmdlet arguments. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the System user. Exploitation of the vulnerability requires an authenticated user in a certain Exchange role to be compromised. The security update addresses the vulnerability by correcting how Microsoft Exchange handles cmdlet arguments.

Frequently asked questions

What is CVE-2020-16875?: A remote code execution vulnerability exists in Microsoft Exchange server due to improper validation of cmdlet arguments. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the System user. Exploitation of the vulnerability requires an authenticated user in a certain Exchange role to be compromised. The security update addresses the vulnerability by correcting how Microsoft Exchange handles cmdlet arguments.
How severe is CVE-2020-16875?: CVE-2020-16875 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-16875 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 47% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-16875?: CVE-2020-16875 primarily affects Microsoft Exchange Server. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-16875?: 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-2020-16875 published?: CVE-2020-16875 was published on 2020-09-11 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_16:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2016:cumulative_update_17:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_5:*:*:*:*:*:*
cpe:2.3:a:microsoft:exchange_server:2019:cumulative_update_6:*:*:*:*:*:*

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