How severe is CVE-2021-1421?

CVE-2021-1421 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-1421 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1421?

CVE-2021-1421 affects Cisco Enterprise Nfv Infrastructure Software. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-1421?

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-2021-1421 published?

CVE-2021-1421 was published on 2021-05-06 and last updated on 2026-06-17.

CVE-2021-1421

CVE-2021-1421 is a high-severity vulnerability in Cisco Enterprise Nfv Infrastructure Software with a CVSS 3.x base score of 7.8. 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 7.8)
CVSS v2: 7.2
EPSS exploit prediction: 1% (47th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Cisco Enterprise Nfv Infrastructure Software
Published: 2021-05-06
Last modified: 2026-06-17

Description

A vulnerability in Cisco Enterprise NFV Infrastructure Software (NFVIS) could allow an authenticated, local attacker to perform a command injection attack on an affected device. The vulnerability is due to insufficient validation of user-supplied input to a configuration command. An attacker could exploit this vulnerability by including malicious input during the execution of this command. A successful exploit could allow a non-privileged attacker authenticated in the restricted CLI to execute arbitrary commands on the underlying operating system (OS) with root privileges.

Frequently asked questions

What is CVE-2021-1421?: A vulnerability in Cisco Enterprise NFV Infrastructure Software (NFVIS) could allow an authenticated, local attacker to perform a command injection attack on an affected device. The vulnerability is due to insufficient validation of user-supplied input to a configuration command. An attacker could exploit this vulnerability by including malicious input during the execution of this command. A successful exploit could allow a non-privileged attacker authenticated in the restricted CLI to execute arbitrary commands on the underlying operating system (OS) with root privileges.
How severe is CVE-2021-1421?: CVE-2021-1421 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-1421 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1421?: CVE-2021-1421 affects Cisco Enterprise Nfv Infrastructure Software. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-1421?: 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-2021-1421 published?: CVE-2021-1421 was published on 2021-05-06 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-nfvis-cmdinj-DkFjqg2j

Affected products (1)

cpe:2.3:a:cisco:enterprise_nfv_infrastructure_software:*:*:*:*:*:*:*:*

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