How severe is CVE-2021-21976?

CVE-2021-21976 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-21976 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-2021-21976?

CVE-2021-21976 affects Vmware Vsphere Replication. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-21976?

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-2021-21976 published?

CVE-2021-21976 was published on 2021-02-11 and last updated on 2026-06-17.

CVE-2021-21976

CVE-2021-21976 is a high-severity vulnerability in Vmware Vsphere Replication with a CVSS 3.x base score of 7.2. 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-78.

Key facts

Severity: High (CVSS 3.x base score 7.2)
CVSS v2: 6.5
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Vmware Vsphere Replication
Published: 2021-02-11
Last modified: 2026-06-17

Description

vSphere Replication 8.3.x prior to 8.3.1.2, 8.2.x prior to 8.2.1.1, 8.1.x prior to 8.1.2.3 and 6.5.x prior to 6.5.1.5 contain a post-authentication command injection vulnerability which may allow an authenticated admin user to perform a remote code execution.

Frequently asked questions

What is CVE-2021-21976?: vSphere Replication 8.3.x prior to 8.3.1.2, 8.2.x prior to 8.2.1.1, 8.1.x prior to 8.1.2.3 and 6.5.x prior to 6.5.1.5 contain a post-authentication command injection vulnerability which may allow an authenticated admin user to perform a remote code execution.
How severe is CVE-2021-21976?: CVE-2021-21976 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-21976 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-2021-21976?: CVE-2021-21976 affects Vmware Vsphere Replication. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-21976?: 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-2021-21976 published?: CVE-2021-21976 was published on 2021-02-11 and last updated on 2026-06-17.

References

https://www.vmware.com/security/advisories/VMSA-2021-0001.html

Affected products (1)

cpe:2.3:a:vmware:vsphere_replication:*:*:*:*:*:*:*:*

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