How severe is CVE-2021-21978?

CVE-2021-21978 has a CVSS 3.x base score of 9.8, 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-2021-21978 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 99% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21978?

CVE-2021-21978 primarily affects Vmware View Planner. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-21978?

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-2021-21978 published?

CVE-2021-21978 was published on 2021-03-03 and last updated on 2026-06-17.

CVE-2021-21978

CVE-2021-21978 is a critical-severity vulnerability in Vmware View Planner with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 99% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 99% (100th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Vmware View Planner
Published: 2021-03-03
Last modified: 2026-06-17

Description

VMware View Planner 4.x prior to 4.6 Security Patch 1 contains a remote code execution vulnerability. Improper input validation and lack of authorization leading to arbitrary file upload in logupload web application. An unauthorized attacker with network access to View Planner Harness could upload and execute a specially crafted file leading to remote code execution within the logupload container.

Frequently asked questions

What is CVE-2021-21978?: VMware View Planner 4.x prior to 4.6 Security Patch 1 contains a remote code execution vulnerability. Improper input validation and lack of authorization leading to arbitrary file upload in logupload web application. An unauthorized attacker with network access to View Planner Harness could upload and execute a specially crafted file leading to remote code execution within the logupload container.
How severe is CVE-2021-21978?: CVE-2021-21978 has a CVSS 3.x base score of 9.8, 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-2021-21978 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 99% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21978?: CVE-2021-21978 primarily affects Vmware View Planner. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-21978?: 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-2021-21978 published?: CVE-2021-21978 was published on 2021-03-03 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:vmware:view_planner:*:*:*:*:*:*:*:*
cpe:2.3:a:vmware:view_planner:4.6:-:*:*:*:*:*:*

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